diff --git a/Makefile.in b/Makefile.in
index 5e37a781e1..cf9010566b 100644
--- a/Makefile.in
+++ b/Makefile.in
@@ -4325,7 +4325,7 @@ COND_USE_GUI_1___MONOLIB_GUI_SRC_OBJECTS =  \
 	monodll_ribbon_control.o \
 	monodll_gallery.o \
 	monodll_page.o \
-	monodll_ribbon_panel.o \
+	monodll_panel.o \
 	monodll_ribbon_toolbar.o \
 	monodll_xh_ribbon.o \
 	monodll_richtextbuffer.o \
@@ -5357,7 +5357,6 @@ COND_TOOLKIT_MSW___GUI_SRC_OBJECTS =  \
 	monodll_msw_notebook.o \
 	monodll_access.o \
 	monodll_ownerdrw.o \
-	monodll_msw_panel.o \
 	monodll_progdlg.o \
 	monodll_msw_radiobox.o \
 	monodll_msw_radiobut.o \
@@ -6347,7 +6346,7 @@ COND_USE_GUI_1___MONOLIB_GUI_SRC_OBJECTS_1 =  \
 	monolib_ribbon_control.o \
 	monolib_gallery.o \
 	monolib_page.o \
-	monolib_ribbon_panel.o \
+	monolib_panel.o \
 	monolib_ribbon_toolbar.o \
 	monolib_xh_ribbon.o \
 	monolib_richtextbuffer.o \
@@ -7379,7 +7378,6 @@ COND_TOOLKIT_MSW___GUI_SRC_OBJECTS_1 =  \
 	monolib_msw_notebook.o \
 	monolib_access.o \
 	monolib_ownerdrw.o \
-	monolib_msw_panel.o \
 	monolib_progdlg.o \
 	monolib_msw_radiobox.o \
 	monolib_msw_radiobut.o \
@@ -9545,7 +9543,6 @@ COND_TOOLKIT_MSW___GUI_SRC_OBJECTS_2 =  \
 	coredll_msw_notebook.o \
 	coredll_access.o \
 	coredll_ownerdrw.o \
-	coredll_panel.o \
 	coredll_progdlg.o \
 	coredll_msw_radiobox.o \
 	coredll_msw_radiobut.o \
@@ -11019,7 +11016,6 @@ COND_TOOLKIT_MSW___GUI_SRC_OBJECTS_3 =  \
 	corelib_msw_notebook.o \
 	corelib_access.o \
 	corelib_ownerdrw.o \
-	corelib_panel.o \
 	corelib_progdlg.o \
 	corelib_msw_radiobox.o \
 	corelib_msw_radiobut.o \
@@ -16396,9 +16392,6 @@ monodll_access.o: $(srcdir)/src/msw/ole/access.cpp $(MONODLL_ODEP)
 monodll_ownerdrw.o: $(srcdir)/src/msw/ownerdrw.cpp $(MONODLL_ODEP)
 	$(CXXC) -c -o $@ $(MONODLL_CXXFLAGS) $(srcdir)/src/msw/ownerdrw.cpp
 
-monodll_msw_panel.o: $(srcdir)/src/msw/panel.cpp $(MONODLL_ODEP)
-	$(CXXC) -c -o $@ $(MONODLL_CXXFLAGS) $(srcdir)/src/msw/panel.cpp
-
 monodll_progdlg.o: $(srcdir)/src/msw/progdlg.cpp $(MONODLL_ODEP)
 	$(CXXC) -c -o $@ $(MONODLL_CXXFLAGS) $(srcdir)/src/msw/progdlg.cpp
 
@@ -17182,7 +17175,7 @@ monodll_gallery.o: $(srcdir)/src/ribbon/gallery.cpp $(MONODLL_ODEP)
 monodll_page.o: $(srcdir)/src/ribbon/page.cpp $(MONODLL_ODEP)
 	$(CXXC) -c -o $@ $(MONODLL_CXXFLAGS) $(srcdir)/src/ribbon/page.cpp
 
-monodll_ribbon_panel.o: $(srcdir)/src/ribbon/panel.cpp $(MONODLL_ODEP)
+monodll_panel.o: $(srcdir)/src/ribbon/panel.cpp $(MONODLL_ODEP)
 	$(CXXC) -c -o $@ $(MONODLL_CXXFLAGS) $(srcdir)/src/ribbon/panel.cpp
 
 monodll_ribbon_toolbar.o: $(srcdir)/src/ribbon/toolbar.cpp $(MONODLL_ODEP)
@@ -21247,9 +21240,6 @@ monolib_access.o: $(srcdir)/src/msw/ole/access.cpp $(MONOLIB_ODEP)
 monolib_ownerdrw.o: $(srcdir)/src/msw/ownerdrw.cpp $(MONOLIB_ODEP)
 	$(CXXC) -c -o $@ $(MONOLIB_CXXFLAGS) $(srcdir)/src/msw/ownerdrw.cpp
 
-monolib_msw_panel.o: $(srcdir)/src/msw/panel.cpp $(MONOLIB_ODEP)
-	$(CXXC) -c -o $@ $(MONOLIB_CXXFLAGS) $(srcdir)/src/msw/panel.cpp
-
 monolib_progdlg.o: $(srcdir)/src/msw/progdlg.cpp $(MONOLIB_ODEP)
 	$(CXXC) -c -o $@ $(MONOLIB_CXXFLAGS) $(srcdir)/src/msw/progdlg.cpp
 
@@ -22033,7 +22023,7 @@ monolib_gallery.o: $(srcdir)/src/ribbon/gallery.cpp $(MONOLIB_ODEP)
 monolib_page.o: $(srcdir)/src/ribbon/page.cpp $(MONOLIB_ODEP)
 	$(CXXC) -c -o $@ $(MONOLIB_CXXFLAGS) $(srcdir)/src/ribbon/page.cpp
 
-monolib_ribbon_panel.o: $(srcdir)/src/ribbon/panel.cpp $(MONOLIB_ODEP)
+monolib_panel.o: $(srcdir)/src/ribbon/panel.cpp $(MONOLIB_ODEP)
 	$(CXXC) -c -o $@ $(MONOLIB_CXXFLAGS) $(srcdir)/src/ribbon/panel.cpp
 
 monolib_ribbon_toolbar.o: $(srcdir)/src/ribbon/toolbar.cpp $(MONOLIB_ODEP)
@@ -26761,9 +26751,6 @@ coredll_access.o: $(srcdir)/src/msw/ole/access.cpp $(COREDLL_ODEP)
 coredll_ownerdrw.o: $(srcdir)/src/msw/ownerdrw.cpp $(COREDLL_ODEP)
 	$(CXXC) -c -o $@ $(COREDLL_CXXFLAGS) $(srcdir)/src/msw/ownerdrw.cpp
 
-coredll_panel.o: $(srcdir)/src/msw/panel.cpp $(COREDLL_ODEP)
-	$(CXXC) -c -o $@ $(COREDLL_CXXFLAGS) $(srcdir)/src/msw/panel.cpp
-
 coredll_progdlg.o: $(srcdir)/src/msw/progdlg.cpp $(COREDLL_ODEP)
 	$(CXXC) -c -o $@ $(COREDLL_CXXFLAGS) $(srcdir)/src/msw/progdlg.cpp
 
@@ -30157,9 +30144,6 @@ corelib_access.o: $(srcdir)/src/msw/ole/access.cpp $(CORELIB_ODEP)
 corelib_ownerdrw.o: $(srcdir)/src/msw/ownerdrw.cpp $(CORELIB_ODEP)
 	$(CXXC) -c -o $@ $(CORELIB_CXXFLAGS) $(srcdir)/src/msw/ownerdrw.cpp
 
-corelib_panel.o: $(srcdir)/src/msw/panel.cpp $(CORELIB_ODEP)
-	$(CXXC) -c -o $@ $(CORELIB_CXXFLAGS) $(srcdir)/src/msw/panel.cpp
-
 corelib_progdlg.o: $(srcdir)/src/msw/progdlg.cpp $(CORELIB_ODEP)
 	$(CXXC) -c -o $@ $(CORELIB_CXXFLAGS) $(srcdir)/src/msw/progdlg.cpp
 
diff --git a/build/bakefiles/files.bkl b/build/bakefiles/files.bkl
index 99f3c3231c..609ede490d 100644
--- a/build/bakefiles/files.bkl
+++ b/build/bakefiles/files.bkl
@@ -1969,7 +1969,6 @@ IMPORTANT: please read docs/tech/tn0016.txt before modifying this file!
     src/msw/notebook.cpp
     src/msw/ole/access.cpp
     src/msw/ownerdrw.cpp
-    src/msw/panel.cpp
     src/msw/progdlg.cpp
     src/msw/radiobox.cpp
     src/msw/radiobut.cpp
diff --git a/build/files b/build/files
index 7fcb062989..af994ad48a 100644
--- a/build/files
+++ b/build/files
@@ -1827,7 +1827,6 @@ MSW_SRC =
     src/msw/notebook.cpp
     src/msw/ole/access.cpp
     src/msw/ownerdrw.cpp
-    src/msw/panel.cpp
     src/msw/progdlg.cpp
     src/msw/radiobox.cpp
     src/msw/radiobut.cpp
diff --git a/build/msw/makefile.bcc b/build/msw/makefile.bcc
index 0d649544fc..fe3d0a2a44 100644
--- a/build/msw/makefile.bcc
+++ b/build/msw/makefile.bcc
@@ -1772,7 +1772,7 @@ ____MONOLIB_GUI_SRC_FILENAMES_OBJECTS =  \
 	$(OBJS)\monodll_ribbon_control.obj \
 	$(OBJS)\monodll_gallery.obj \
 	$(OBJS)\monodll_page.obj \
-	$(OBJS)\monodll_ribbon_panel.obj \
+	$(OBJS)\monodll_panel.obj \
 	$(OBJS)\monodll_ribbon_toolbar.obj \
 	$(OBJS)\monodll_xh_ribbon.obj \
 	$(OBJS)\monodll_richtextbuffer.obj \
@@ -1887,7 +1887,6 @@ ____CORE_SRC_FILENAMES_OBJECTS =  \
 	$(OBJS)\monodll_msw_notebook.obj \
 	$(OBJS)\monodll_access.obj \
 	$(OBJS)\monodll_ownerdrw.obj \
-	$(OBJS)\monodll_msw_panel.obj \
 	$(OBJS)\monodll_progdlg.obj \
 	$(OBJS)\monodll_msw_radiobox.obj \
 	$(OBJS)\monodll_msw_radiobut.obj \
@@ -2604,7 +2603,7 @@ ____MONOLIB_GUI_SRC_FILENAMES_1_OBJECTS =  \
 	$(OBJS)\monolib_ribbon_control.obj \
 	$(OBJS)\monolib_gallery.obj \
 	$(OBJS)\monolib_page.obj \
-	$(OBJS)\monolib_ribbon_panel.obj \
+	$(OBJS)\monolib_panel.obj \
 	$(OBJS)\monolib_ribbon_toolbar.obj \
 	$(OBJS)\monolib_xh_ribbon.obj \
 	$(OBJS)\monolib_richtextbuffer.obj \
@@ -2719,7 +2718,6 @@ ____CORE_SRC_FILENAMES_1_OBJECTS =  \
 	$(OBJS)\monolib_msw_notebook.obj \
 	$(OBJS)\monolib_access.obj \
 	$(OBJS)\monolib_ownerdrw.obj \
-	$(OBJS)\monolib_msw_panel.obj \
 	$(OBJS)\monolib_progdlg.obj \
 	$(OBJS)\monolib_msw_radiobox.obj \
 	$(OBJS)\monolib_msw_radiobut.obj \
@@ -3423,7 +3421,6 @@ ____CORE_SRC_FILENAMES_2_OBJECTS =  \
 	$(OBJS)\coredll_msw_notebook.obj \
 	$(OBJS)\coredll_access.obj \
 	$(OBJS)\coredll_ownerdrw.obj \
-	$(OBJS)\coredll_panel.obj \
 	$(OBJS)\coredll_progdlg.obj \
 	$(OBJS)\coredll_msw_radiobox.obj \
 	$(OBJS)\coredll_msw_radiobut.obj \
@@ -3995,7 +3992,6 @@ ____CORE_SRC_FILENAMES_3_OBJECTS =  \
 	$(OBJS)\corelib_msw_notebook.obj \
 	$(OBJS)\corelib_access.obj \
 	$(OBJS)\corelib_ownerdrw.obj \
-	$(OBJS)\corelib_panel.obj \
 	$(OBJS)\corelib_progdlg.obj \
 	$(OBJS)\corelib_msw_radiobox.obj \
 	$(OBJS)\corelib_msw_radiobut.obj \
@@ -6888,9 +6884,6 @@ $(OBJS)\monodll_access.obj: ..\..\src\msw\ole\access.cpp
 $(OBJS)\monodll_ownerdrw.obj: ..\..\src\msw\ownerdrw.cpp
 	$(CXX) -q -c -P -o$@ $(MONODLL_CXXFLAGS) ..\..\src\msw\ownerdrw.cpp
 
-$(OBJS)\monodll_msw_panel.obj: ..\..\src\msw\panel.cpp
-	$(CXX) -q -c -P -o$@ $(MONODLL_CXXFLAGS) ..\..\src\msw\panel.cpp
-
 $(OBJS)\monodll_progdlg.obj: ..\..\src\msw\progdlg.cpp
 	$(CXX) -q -c -P -o$@ $(MONODLL_CXXFLAGS) ..\..\src\msw\progdlg.cpp
 
@@ -7527,7 +7520,7 @@ $(OBJS)\monodll_gallery.obj: ..\..\src\ribbon\gallery.cpp
 $(OBJS)\monodll_page.obj: ..\..\src\ribbon\page.cpp
 	$(CXX) -q -c -P -o$@ $(MONODLL_CXXFLAGS) ..\..\src\ribbon\page.cpp
 
-$(OBJS)\monodll_ribbon_panel.obj: ..\..\src\ribbon\panel.cpp
+$(OBJS)\monodll_panel.obj: ..\..\src\ribbon\panel.cpp
 	$(CXX) -q -c -P -o$@ $(MONODLL_CXXFLAGS) ..\..\src\ribbon\panel.cpp
 
 $(OBJS)\monodll_ribbon_toolbar.obj: ..\..\src\ribbon\toolbar.cpp
@@ -9432,9 +9425,6 @@ $(OBJS)\monolib_access.obj: ..\..\src\msw\ole\access.cpp
 $(OBJS)\monolib_ownerdrw.obj: ..\..\src\msw\ownerdrw.cpp
 	$(CXX) -q -c -P -o$@ $(MONOLIB_CXXFLAGS) ..\..\src\msw\ownerdrw.cpp
 
-$(OBJS)\monolib_msw_panel.obj: ..\..\src\msw\panel.cpp
-	$(CXX) -q -c -P -o$@ $(MONOLIB_CXXFLAGS) ..\..\src\msw\panel.cpp
-
 $(OBJS)\monolib_progdlg.obj: ..\..\src\msw\progdlg.cpp
 	$(CXX) -q -c -P -o$@ $(MONOLIB_CXXFLAGS) ..\..\src\msw\progdlg.cpp
 
@@ -10071,7 +10061,7 @@ $(OBJS)\monolib_gallery.obj: ..\..\src\ribbon\gallery.cpp
 $(OBJS)\monolib_page.obj: ..\..\src\ribbon\page.cpp
 	$(CXX) -q -c -P -o$@ $(MONOLIB_CXXFLAGS) ..\..\src\ribbon\page.cpp
 
-$(OBJS)\monolib_ribbon_panel.obj: ..\..\src\ribbon\panel.cpp
+$(OBJS)\monolib_panel.obj: ..\..\src\ribbon\panel.cpp
 	$(CXX) -q -c -P -o$@ $(MONOLIB_CXXFLAGS) ..\..\src\ribbon\panel.cpp
 
 $(OBJS)\monolib_ribbon_toolbar.obj: ..\..\src\ribbon\toolbar.cpp
@@ -12390,9 +12380,6 @@ $(OBJS)\coredll_access.obj: ..\..\src\msw\ole\access.cpp
 $(OBJS)\coredll_ownerdrw.obj: ..\..\src\msw\ownerdrw.cpp
 	$(CXX) -q -c -P -o$@ $(COREDLL_CXXFLAGS) ..\..\src\msw\ownerdrw.cpp
 
-$(OBJS)\coredll_panel.obj: ..\..\src\msw\panel.cpp
-	$(CXX) -q -c -P -o$@ $(COREDLL_CXXFLAGS) ..\..\src\msw\panel.cpp
-
 $(OBJS)\coredll_progdlg.obj: ..\..\src\msw\progdlg.cpp
 	$(CXX) -q -c -P -o$@ $(COREDLL_CXXFLAGS) ..\..\src\msw\progdlg.cpp
 
@@ -13870,9 +13857,6 @@ $(OBJS)\corelib_access.obj: ..\..\src\msw\ole\access.cpp
 $(OBJS)\corelib_ownerdrw.obj: ..\..\src\msw\ownerdrw.cpp
 	$(CXX) -q -c -P -o$@ $(CORELIB_CXXFLAGS) ..\..\src\msw\ownerdrw.cpp
 
-$(OBJS)\corelib_panel.obj: ..\..\src\msw\panel.cpp
-	$(CXX) -q -c -P -o$@ $(CORELIB_CXXFLAGS) ..\..\src\msw\panel.cpp
-
 $(OBJS)\corelib_progdlg.obj: ..\..\src\msw\progdlg.cpp
 	$(CXX) -q -c -P -o$@ $(CORELIB_CXXFLAGS) ..\..\src\msw\progdlg.cpp
 
diff --git a/build/msw/makefile.gcc b/build/msw/makefile.gcc
index 02d6ba2299..6a988817c3 100644
--- a/build/msw/makefile.gcc
+++ b/build/msw/makefile.gcc
@@ -1791,7 +1791,7 @@ ____MONOLIB_GUI_SRC_FILENAMES_OBJECTS =  \
 	$(OBJS)\monodll_ribbon_control.o \
 	$(OBJS)\monodll_gallery.o \
 	$(OBJS)\monodll_page.o \
-	$(OBJS)\monodll_ribbon_panel.o \
+	$(OBJS)\monodll_panel.o \
 	$(OBJS)\monodll_ribbon_toolbar.o \
 	$(OBJS)\monodll_xh_ribbon.o \
 	$(OBJS)\monodll_richtextbuffer.o \
@@ -1907,7 +1907,6 @@ ____CORE_SRC_FILENAMES_OBJECTS =  \
 	$(OBJS)\monodll_msw_notebook.o \
 	$(OBJS)\monodll_access.o \
 	$(OBJS)\monodll_ownerdrw.o \
-	$(OBJS)\monodll_msw_panel.o \
 	$(OBJS)\monodll_progdlg.o \
 	$(OBJS)\monodll_msw_radiobox.o \
 	$(OBJS)\monodll_msw_radiobut.o \
@@ -2629,7 +2628,7 @@ ____MONOLIB_GUI_SRC_FILENAMES_1_OBJECTS =  \
 	$(OBJS)\monolib_ribbon_control.o \
 	$(OBJS)\monolib_gallery.o \
 	$(OBJS)\monolib_page.o \
-	$(OBJS)\monolib_ribbon_panel.o \
+	$(OBJS)\monolib_panel.o \
 	$(OBJS)\monolib_ribbon_toolbar.o \
 	$(OBJS)\monolib_xh_ribbon.o \
 	$(OBJS)\monolib_richtextbuffer.o \
@@ -2745,7 +2744,6 @@ ____CORE_SRC_FILENAMES_1_OBJECTS =  \
 	$(OBJS)\monolib_msw_notebook.o \
 	$(OBJS)\monolib_access.o \
 	$(OBJS)\monolib_ownerdrw.o \
-	$(OBJS)\monolib_msw_panel.o \
 	$(OBJS)\monolib_progdlg.o \
 	$(OBJS)\monolib_msw_radiobox.o \
 	$(OBJS)\monolib_msw_radiobut.o \
@@ -3465,7 +3463,6 @@ ____CORE_SRC_FILENAMES_2_OBJECTS =  \
 	$(OBJS)\coredll_msw_notebook.o \
 	$(OBJS)\coredll_access.o \
 	$(OBJS)\coredll_ownerdrw.o \
-	$(OBJS)\coredll_panel.o \
 	$(OBJS)\coredll_progdlg.o \
 	$(OBJS)\coredll_msw_radiobox.o \
 	$(OBJS)\coredll_msw_radiobut.o \
@@ -4045,7 +4042,6 @@ ____CORE_SRC_FILENAMES_3_OBJECTS =  \
 	$(OBJS)\corelib_msw_notebook.o \
 	$(OBJS)\corelib_access.o \
 	$(OBJS)\corelib_ownerdrw.o \
-	$(OBJS)\corelib_panel.o \
 	$(OBJS)\corelib_progdlg.o \
 	$(OBJS)\corelib_msw_radiobox.o \
 	$(OBJS)\corelib_msw_radiobut.o \
@@ -7064,9 +7060,6 @@ $(OBJS)\monodll_access.o: ../../src/msw/ole/access.cpp
 $(OBJS)\monodll_ownerdrw.o: ../../src/msw/ownerdrw.cpp
 	$(CXX) -c -o $@ $(MONODLL_CXXFLAGS) $(CPPDEPS) $<
 
-$(OBJS)\monodll_msw_panel.o: ../../src/msw/panel.cpp
-	$(CXX) -c -o $@ $(MONODLL_CXXFLAGS) $(CPPDEPS) $<
-
 $(OBJS)\monodll_progdlg.o: ../../src/msw/progdlg.cpp
 	$(CXX) -c -o $@ $(MONODLL_CXXFLAGS) $(CPPDEPS) $<
 
@@ -7703,7 +7696,7 @@ $(OBJS)\monodll_gallery.o: ../../src/ribbon/gallery.cpp
 $(OBJS)\monodll_page.o: ../../src/ribbon/page.cpp
 	$(CXX) -c -o $@ $(MONODLL_CXXFLAGS) $(CPPDEPS) $<
 
-$(OBJS)\monodll_ribbon_panel.o: ../../src/ribbon/panel.cpp
+$(OBJS)\monodll_panel.o: ../../src/ribbon/panel.cpp
 	$(CXX) -c -o $@ $(MONODLL_CXXFLAGS) $(CPPDEPS) $<
 
 $(OBJS)\monodll_ribbon_toolbar.o: ../../src/ribbon/toolbar.cpp
@@ -9610,9 +9603,6 @@ $(OBJS)\monolib_access.o: ../../src/msw/ole/access.cpp
 $(OBJS)\monolib_ownerdrw.o: ../../src/msw/ownerdrw.cpp
 	$(CXX) -c -o $@ $(MONOLIB_CXXFLAGS) $(CPPDEPS) $<
 
-$(OBJS)\monolib_msw_panel.o: ../../src/msw/panel.cpp
-	$(CXX) -c -o $@ $(MONOLIB_CXXFLAGS) $(CPPDEPS) $<
-
 $(OBJS)\monolib_progdlg.o: ../../src/msw/progdlg.cpp
 	$(CXX) -c -o $@ $(MONOLIB_CXXFLAGS) $(CPPDEPS) $<
 
@@ -10249,7 +10239,7 @@ $(OBJS)\monolib_gallery.o: ../../src/ribbon/gallery.cpp
 $(OBJS)\monolib_page.o: ../../src/ribbon/page.cpp
 	$(CXX) -c -o $@ $(MONOLIB_CXXFLAGS) $(CPPDEPS) $<
 
-$(OBJS)\monolib_ribbon_panel.o: ../../src/ribbon/panel.cpp
+$(OBJS)\monolib_panel.o: ../../src/ribbon/panel.cpp
 	$(CXX) -c -o $@ $(MONOLIB_CXXFLAGS) $(CPPDEPS) $<
 
 $(OBJS)\monolib_ribbon_toolbar.o: ../../src/ribbon/toolbar.cpp
@@ -12570,9 +12560,6 @@ $(OBJS)\coredll_access.o: ../../src/msw/ole/access.cpp
 $(OBJS)\coredll_ownerdrw.o: ../../src/msw/ownerdrw.cpp
 	$(CXX) -c -o $@ $(COREDLL_CXXFLAGS) $(CPPDEPS) $<
 
-$(OBJS)\coredll_panel.o: ../../src/msw/panel.cpp
-	$(CXX) -c -o $@ $(COREDLL_CXXFLAGS) $(CPPDEPS) $<
-
 $(OBJS)\coredll_progdlg.o: ../../src/msw/progdlg.cpp
 	$(CXX) -c -o $@ $(COREDLL_CXXFLAGS) $(CPPDEPS) $<
 
@@ -14050,9 +14037,6 @@ $(OBJS)\corelib_access.o: ../../src/msw/ole/access.cpp
 $(OBJS)\corelib_ownerdrw.o: ../../src/msw/ownerdrw.cpp
 	$(CXX) -c -o $@ $(CORELIB_CXXFLAGS) $(CPPDEPS) $<
 
-$(OBJS)\corelib_panel.o: ../../src/msw/panel.cpp
-	$(CXX) -c -o $@ $(CORELIB_CXXFLAGS) $(CPPDEPS) $<
-
 $(OBJS)\corelib_progdlg.o: ../../src/msw/progdlg.cpp
 	$(CXX) -c -o $@ $(CORELIB_CXXFLAGS) $(CPPDEPS) $<
 
diff --git a/build/msw/makefile.vc b/build/msw/makefile.vc
index 0ec2923388..1fd3de3824 100644
--- a/build/msw/makefile.vc
+++ b/build/msw/makefile.vc
@@ -2073,7 +2073,7 @@ ____MONOLIB_GUI_SRC_FILENAMES_OBJECTS =  \
 	$(OBJS)\monodll_ribbon_control.obj \
 	$(OBJS)\monodll_gallery.obj \
 	$(OBJS)\monodll_page.obj \
-	$(OBJS)\monodll_ribbon_panel.obj \
+	$(OBJS)\monodll_panel.obj \
 	$(OBJS)\monodll_ribbon_toolbar.obj \
 	$(OBJS)\monodll_xh_ribbon.obj \
 	$(OBJS)\monodll_richtextbuffer.obj \
@@ -2188,7 +2188,6 @@ ____CORE_SRC_FILENAMES_OBJECTS =  \
 	$(OBJS)\monodll_msw_notebook.obj \
 	$(OBJS)\monodll_access.obj \
 	$(OBJS)\monodll_ownerdrw.obj \
-	$(OBJS)\monodll_msw_panel.obj \
 	$(OBJS)\monodll_progdlg.obj \
 	$(OBJS)\monodll_msw_radiobox.obj \
 	$(OBJS)\monodll_msw_radiobut.obj \
@@ -2911,7 +2910,7 @@ ____MONOLIB_GUI_SRC_FILENAMES_1_OBJECTS =  \
 	$(OBJS)\monolib_ribbon_control.obj \
 	$(OBJS)\monolib_gallery.obj \
 	$(OBJS)\monolib_page.obj \
-	$(OBJS)\monolib_ribbon_panel.obj \
+	$(OBJS)\monolib_panel.obj \
 	$(OBJS)\monolib_ribbon_toolbar.obj \
 	$(OBJS)\monolib_xh_ribbon.obj \
 	$(OBJS)\monolib_richtextbuffer.obj \
@@ -3026,7 +3025,6 @@ ____CORE_SRC_FILENAMES_1_OBJECTS =  \
 	$(OBJS)\monolib_msw_notebook.obj \
 	$(OBJS)\monolib_access.obj \
 	$(OBJS)\monolib_ownerdrw.obj \
-	$(OBJS)\monolib_msw_panel.obj \
 	$(OBJS)\monolib_progdlg.obj \
 	$(OBJS)\monolib_msw_radiobox.obj \
 	$(OBJS)\monolib_msw_radiobut.obj \
@@ -3796,7 +3794,6 @@ ____CORE_SRC_FILENAMES_2_OBJECTS =  \
 	$(OBJS)\coredll_msw_notebook.obj \
 	$(OBJS)\coredll_access.obj \
 	$(OBJS)\coredll_ownerdrw.obj \
-	$(OBJS)\coredll_panel.obj \
 	$(OBJS)\coredll_progdlg.obj \
 	$(OBJS)\coredll_msw_radiobox.obj \
 	$(OBJS)\coredll_msw_radiobut.obj \
@@ -4374,7 +4371,6 @@ ____CORE_SRC_FILENAMES_3_OBJECTS =  \
 	$(OBJS)\corelib_msw_notebook.obj \
 	$(OBJS)\corelib_access.obj \
 	$(OBJS)\corelib_ownerdrw.obj \
-	$(OBJS)\corelib_panel.obj \
 	$(OBJS)\corelib_progdlg.obj \
 	$(OBJS)\corelib_msw_radiobox.obj \
 	$(OBJS)\corelib_msw_radiobut.obj \
@@ -7581,9 +7577,6 @@ $(OBJS)\monodll_access.obj: ..\..\src\msw\ole\access.cpp
 $(OBJS)\monodll_ownerdrw.obj: ..\..\src\msw\ownerdrw.cpp
 	$(CXX) /c /nologo /TP /Fo$@ $(MONODLL_CXXFLAGS) ..\..\src\msw\ownerdrw.cpp
 
-$(OBJS)\monodll_msw_panel.obj: ..\..\src\msw\panel.cpp
-	$(CXX) /c /nologo /TP /Fo$@ $(MONODLL_CXXFLAGS) ..\..\src\msw\panel.cpp
-
 $(OBJS)\monodll_progdlg.obj: ..\..\src\msw\progdlg.cpp
 	$(CXX) /c /nologo /TP /Fo$@ $(MONODLL_CXXFLAGS) ..\..\src\msw\progdlg.cpp
 
@@ -8220,7 +8213,7 @@ $(OBJS)\monodll_gallery.obj: ..\..\src\ribbon\gallery.cpp
 $(OBJS)\monodll_page.obj: ..\..\src\ribbon\page.cpp
 	$(CXX) /c /nologo /TP /Fo$@ $(MONODLL_CXXFLAGS) ..\..\src\ribbon\page.cpp
 
-$(OBJS)\monodll_ribbon_panel.obj: ..\..\src\ribbon\panel.cpp
+$(OBJS)\monodll_panel.obj: ..\..\src\ribbon\panel.cpp
 	$(CXX) /c /nologo /TP /Fo$@ $(MONODLL_CXXFLAGS) ..\..\src\ribbon\panel.cpp
 
 $(OBJS)\monodll_ribbon_toolbar.obj: ..\..\src\ribbon\toolbar.cpp
@@ -10125,9 +10118,6 @@ $(OBJS)\monolib_access.obj: ..\..\src\msw\ole\access.cpp
 $(OBJS)\monolib_ownerdrw.obj: ..\..\src\msw\ownerdrw.cpp
 	$(CXX) /c /nologo /TP /Fo$@ $(MONOLIB_CXXFLAGS) ..\..\src\msw\ownerdrw.cpp
 
-$(OBJS)\monolib_msw_panel.obj: ..\..\src\msw\panel.cpp
-	$(CXX) /c /nologo /TP /Fo$@ $(MONOLIB_CXXFLAGS) ..\..\src\msw\panel.cpp
-
 $(OBJS)\monolib_progdlg.obj: ..\..\src\msw\progdlg.cpp
 	$(CXX) /c /nologo /TP /Fo$@ $(MONOLIB_CXXFLAGS) ..\..\src\msw\progdlg.cpp
 
@@ -10764,7 +10754,7 @@ $(OBJS)\monolib_gallery.obj: ..\..\src\ribbon\gallery.cpp
 $(OBJS)\monolib_page.obj: ..\..\src\ribbon\page.cpp
 	$(CXX) /c /nologo /TP /Fo$@ $(MONOLIB_CXXFLAGS) ..\..\src\ribbon\page.cpp
 
-$(OBJS)\monolib_ribbon_panel.obj: ..\..\src\ribbon\panel.cpp
+$(OBJS)\monolib_panel.obj: ..\..\src\ribbon\panel.cpp
 	$(CXX) /c /nologo /TP /Fo$@ $(MONOLIB_CXXFLAGS) ..\..\src\ribbon\panel.cpp
 
 $(OBJS)\monolib_ribbon_toolbar.obj: ..\..\src\ribbon\toolbar.cpp
@@ -13083,9 +13073,6 @@ $(OBJS)\coredll_access.obj: ..\..\src\msw\ole\access.cpp
 $(OBJS)\coredll_ownerdrw.obj: ..\..\src\msw\ownerdrw.cpp
 	$(CXX) /c /nologo /TP /Fo$@ $(COREDLL_CXXFLAGS) ..\..\src\msw\ownerdrw.cpp
 
-$(OBJS)\coredll_panel.obj: ..\..\src\msw\panel.cpp
-	$(CXX) /c /nologo /TP /Fo$@ $(COREDLL_CXXFLAGS) ..\..\src\msw\panel.cpp
-
 $(OBJS)\coredll_progdlg.obj: ..\..\src\msw\progdlg.cpp
 	$(CXX) /c /nologo /TP /Fo$@ $(COREDLL_CXXFLAGS) ..\..\src\msw\progdlg.cpp
 
@@ -14563,9 +14550,6 @@ $(OBJS)\corelib_access.obj: ..\..\src\msw\ole\access.cpp
 $(OBJS)\corelib_ownerdrw.obj: ..\..\src\msw\ownerdrw.cpp
 	$(CXX) /c /nologo /TP /Fo$@ $(CORELIB_CXXFLAGS) ..\..\src\msw\ownerdrw.cpp
 
-$(OBJS)\corelib_panel.obj: ..\..\src\msw\panel.cpp
-	$(CXX) /c /nologo /TP /Fo$@ $(CORELIB_CXXFLAGS) ..\..\src\msw\panel.cpp
-
 $(OBJS)\corelib_progdlg.obj: ..\..\src\msw\progdlg.cpp
 	$(CXX) /c /nologo /TP /Fo$@ $(CORELIB_CXXFLAGS) ..\..\src\msw\progdlg.cpp
 
diff --git a/build/msw/wx_core.vcxproj b/build/msw/wx_core.vcxproj
index 291c6f866d..fc9608749b 100644
--- a/build/msw/wx_core.vcxproj
+++ b/build/msw/wx_core.vcxproj
@@ -799,7 +799,6 @@
     <ClCompile Include="..\..\src\msw\ole\safearray.cpp" />
     <ClCompile Include="..\..\src\msw\ownerdrw.cpp" />
     <ClCompile Include="..\..\src\msw\palette.cpp" />
-    <ClCompile Include="..\..\src\msw\panel.cpp" />
     <ClCompile Include="..\..\src\msw\pen.cpp" />
     <ClCompile Include="..\..\src\msw\popupwin.cpp" />
     <ClCompile Include="..\..\src\msw\printdlg.cpp" />
diff --git a/build/msw/wx_core.vcxproj.filters b/build/msw/wx_core.vcxproj.filters
index 4295676e97..357b1ec0a1 100644
--- a/build/msw/wx_core.vcxproj.filters
+++ b/build/msw/wx_core.vcxproj.filters
@@ -786,9 +786,6 @@
     <ClCompile Include="..\..\src\msw\palette.cpp">
       <Filter>MSW Sources</Filter>
     </ClCompile>
-    <ClCompile Include="..\..\src\msw\panel.cpp">
-      <Filter>MSW Sources</Filter>
-    </ClCompile>
     <ClCompile Include="..\..\src\msw\pen.cpp">
       <Filter>MSW Sources</Filter>
     </ClCompile>
diff --git a/build/msw/wx_vc7_core.vcproj b/build/msw/wx_vc7_core.vcproj
index 583cc7eeee..37d66fa9fd 100644
--- a/build/msw/wx_vc7_core.vcproj
+++ b/build/msw/wx_vc7_core.vcproj
@@ -928,9 +928,6 @@
 			<File
 				RelativePath="..\..\src\msw\palette.cpp">
 			</File>
-			<File
-				RelativePath="..\..\src\msw\panel.cpp">
-			</File>
 			<File
 				RelativePath="..\..\src\msw\pen.cpp">
 			</File>
diff --git a/build/msw/wx_vc8_core.vcproj b/build/msw/wx_vc8_core.vcproj
index 91212e072e..ced19bd2c1 100644
--- a/build/msw/wx_vc8_core.vcproj
+++ b/build/msw/wx_vc8_core.vcproj
@@ -1642,10 +1642,6 @@
 				RelativePath="..\..\src\msw\palette.cpp"
 				>
 			</File>
-			<File
-				RelativePath="..\..\src\msw\panel.cpp"
-				>
-			</File>
 			<File
 				RelativePath="..\..\src\msw\pen.cpp"
 				>
diff --git a/build/msw/wx_vc9_core.vcproj b/build/msw/wx_vc9_core.vcproj
index 91d8b8dbd3..098745f91a 100644
--- a/build/msw/wx_vc9_core.vcproj
+++ b/build/msw/wx_vc9_core.vcproj
@@ -1638,10 +1638,6 @@
 				RelativePath="..\..\src\msw\palette.cpp"
 				>
 			</File>
-			<File
-				RelativePath="..\..\src\msw\panel.cpp"
-				>
-			</File>
 			<File
 				RelativePath="..\..\src\msw\pen.cpp"
 				>
diff --git a/include/wx/containr.h b/include/wx/containr.h
index 784ff2fcd7..bb25e6a42c 100644
--- a/include/wx/containr.h
+++ b/include/wx/containr.h
@@ -90,6 +90,16 @@ public:
     // Returns true if we have any focusable children, false otherwise.
     bool UpdateCanFocusChildren();
 
+#ifdef __WXMSW__
+    // This is not strictly related to navigation, but all windows containing
+    // more than one children controls need to return from this method if any
+    // of their parents has an inheritable background, so do this automatically
+    // for all of them (another alternative could be to do it in wxWindow
+    // itself but this would be potentially more backwards incompatible and
+    // could conceivably break some custom windows).
+    bool HasTransparentBackground() const;
+#endif // __WXMSW__
+
 protected:
     // set the focus to the child which had it the last time
     virtual bool SetFocusToChild();
@@ -252,6 +262,13 @@ public:
         BaseWindowClass::SetFocus();
     }
 
+#ifdef __WXMSW__
+    WXDLLIMPEXP_INLINE_CORE virtual bool HasTransparentBackground() wxOVERRIDE
+    {
+        return m_container.HasTransparentBackground();
+    }
+#endif // __WXMSW__
+
 protected:
 #ifndef wxHAS_NATIVE_TAB_TRAVERSAL
     void OnNavigationKey(wxNavigationKeyEvent& event)
diff --git a/include/wx/msw/panel.h b/include/wx/msw/panel.h
index 4762bef191..86ba5ec6de 100644
--- a/include/wx/msw/panel.h
+++ b/include/wx/msw/panel.h
@@ -31,12 +31,6 @@ public:
         Create(parent, winid, pos, size, style, name);
     }
 
-    // This is overridden for MSW to return true for all panels that are child
-    // of a window with themed background (such as wxNotebook) which should
-    // show through the child panels.
-    virtual bool HasTransparentBackground();
-
-
 #if WXWIN_COMPATIBILITY_2_8
     wxDEPRECATED_CONSTRUCTOR(
     wxPanel(wxWindow *parent,
diff --git a/src/common/containr.cpp b/src/common/containr.cpp
index c663417043..9904c6761a 100644
--- a/src/common/containr.cpp
+++ b/src/common/containr.cpp
@@ -162,6 +162,24 @@ bool wxControlContainerBase::SetFocusToChild()
     return wxSetFocusToChild(m_winParent, &m_winLastFocused);
 }
 
+#ifdef __WXMSW__
+
+bool wxControlContainerBase::HasTransparentBackground() const
+{
+    for ( wxWindow *win = m_winParent->GetParent(); win; win = win->GetParent() )
+    {
+        if ( win->MSWHasInheritableBackground() )
+            return true;
+
+        if ( win->IsTopLevel() )
+            break;
+    }
+
+    return false;
+}
+
+#endif // __WXMSW__
+
 #ifndef wxHAS_NATIVE_TAB_TRAVERSAL
 
 // ----------------------------------------------------------------------------
diff --git a/src/msw/panel.cpp b/src/msw/panel.cpp
deleted file mode 100644
index fc7cfa5bb1..0000000000
--- a/src/msw/panel.cpp
+++ /dev/null
@@ -1,46 +0,0 @@
-///////////////////////////////////////////////////////////////////////////////
-// Name:        src/msw/panel.cpp
-// Purpose:     Implementation of wxMSW-specific wxPanel class.
-// Author:      Vadim Zeitlin
-// Created:     2011-03-18
-// Copyright:   (c) 2011 Vadim Zeitlin <vadim@wxwidgets.org>
-// Licence:     wxWindows licence
-///////////////////////////////////////////////////////////////////////////////
-
-// ============================================================================
-// declarations
-// ============================================================================
-
-// ----------------------------------------------------------------------------
-// headers
-// ----------------------------------------------------------------------------
-
-// for compilers that support precompilation, includes "wx.h".
-#include "wx/wxprec.h"
-
-#ifdef __BORLANDC__
-    #pragma hdrstop
-#endif
-
-#ifndef WX_PRECOMP
-    #include "wx/panel.h"
-#endif // WX_PRECOMP
-
-// ============================================================================
-// implementation
-// ============================================================================
-
-bool wxPanel::HasTransparentBackground()
-{
-    for ( wxWindow *win = GetParent(); win; win = win->GetParent() )
-    {
-        if ( win->MSWHasInheritableBackground() )
-            return true;
-
-        if ( win->IsTopLevel() )
-            break;
-    }
-
-    return false;
-}
-