diff --git a/include/wx/generic/scrolwin.h b/include/wx/generic/scrolwin.h
index 698e8bd824..91c76bbbf3 100644
--- a/include/wx/generic/scrolwin.h
+++ b/include/wx/generic/scrolwin.h
@@ -71,6 +71,14 @@ public:
 
     virtual void DoSetVirtualSize(int x, int y);
 
+    // wxWindow's GetBestVirtualSize returns the actual window size,
+    // whereas we want to return the virtual size
+    virtual wxSize GetBestVirtualSize() const;
+
+    // Return the size best suited for the current window
+    // (this isn't a virtual size, this is a sensible size for the window)
+    virtual wxSize DoGetBestSize() const;
+
 #ifdef __WXMAC__
     virtual bool MacClipChildren() const { return true ; }
 #endif
diff --git a/include/wx/generic/splitter.h b/include/wx/generic/splitter.h
index 12056cac56..2f70ea00e2 100644
--- a/include/wx/generic/splitter.h
+++ b/include/wx/generic/splitter.h
@@ -138,7 +138,7 @@ public:
     bool IsSplit() const { return (m_windowTwo != NULL); }
 
     // Sets the sash size
-    void SetSashSize(int WXUNUSED(width)) { }
+    void SetSashSize(int width) { m_sashSize = width; }
 
     // Sets the border size
     void SetBorderSize(int WXUNUSED(width)) { }
@@ -283,6 +283,7 @@ protected:
     int         m_oldY;
     int         m_sashPosition; // Number of pixels from left or top
     double      m_sashGravity;
+    int         m_sashSize;
     wxSize      m_lastSize;
     int         m_requestedSashPosition;
     int         m_sashPositionCurrent; // while dragging
diff --git a/include/wx/gtk/scrolwin.h b/include/wx/gtk/scrolwin.h
index ecbe811f13..b74c39146c 100644
--- a/include/wx/gtk/scrolwin.h
+++ b/include/wx/gtk/scrolwin.h
@@ -68,6 +68,14 @@ public:
     // Set the scrolled area of the window.
     virtual void DoSetVirtualSize( int x, int y );
 
+    // wxWindow's GetBestVirtualSize returns the actual window size,
+    // whereas we want to return the virtual size
+    virtual wxSize GetBestVirtualSize() const;
+
+    // Return the size best suited for the current window
+    // (this isn't a virtual size, this is a sensible size for the window)
+    virtual wxSize DoGetBestSize() const;
+
     // Set the x, y scrolling increments.
     void SetScrollRate( int xstep, int ystep );
 
diff --git a/include/wx/gtk1/scrolwin.h b/include/wx/gtk1/scrolwin.h
index ecbe811f13..b74c39146c 100644
--- a/include/wx/gtk1/scrolwin.h
+++ b/include/wx/gtk1/scrolwin.h
@@ -68,6 +68,14 @@ public:
     // Set the scrolled area of the window.
     virtual void DoSetVirtualSize( int x, int y );
 
+    // wxWindow's GetBestVirtualSize returns the actual window size,
+    // whereas we want to return the virtual size
+    virtual wxSize GetBestVirtualSize() const;
+
+    // Return the size best suited for the current window
+    // (this isn't a virtual size, this is a sensible size for the window)
+    virtual wxSize DoGetBestSize() const;
+
     // Set the x, y scrolling increments.
     void SetScrollRate( int xstep, int ystep );
 
diff --git a/src/generic/scrlwing.cpp b/src/generic/scrlwing.cpp
index 79b5717aec..4578f66193 100644
--- a/src/generic/scrlwing.cpp
+++ b/src/generic/scrlwing.cpp
@@ -1283,6 +1283,60 @@ void wxGenericScrolledWindow::DoSetVirtualSize(int x, int y)
         Layout();
 }
 
+// wxWindow's GetBestVirtualSize returns the actual window size,
+// whereas we want to return the virtual size
+wxSize wxGenericScrolledWindow::GetBestVirtualSize() const
+{
+    wxSize  clientSize( GetClientSize() );
+    if (GetSizer())
+    {
+        wxSize minSize( GetSizer()->CalcMin() );
+
+        return wxSize( wxMax( clientSize.x, minSize.x ), wxMax( clientSize.y, minSize.y ) );
+    }
+    else
+        return clientSize;
+}
+
+// return the size best suited for the current window
+// (this isn't a virtual size, this is a sensible size for the window)
+wxSize wxGenericScrolledWindow::DoGetBestSize() const
+{
+    wxSize best;
+
+    if ( GetSizer() )
+    {
+        wxSize b = GetSizer()->GetMinSize();
+
+        // Only use the content to set the window size in the direction
+        // where there's no scrolling; otherwise we're going to get a huge
+        // window in the direction in which scrolling is enabled
+        int ppuX, ppuY;
+        GetScrollPixelsPerUnit(& ppuX, & ppuY);
+
+        wxSize minSize;
+        if ( GetMinSize().IsFullySpecified() )
+            minSize = GetMinSize();
+        else
+            minSize = GetSize();
+
+        if (ppuX > 0)
+            b.x = minSize.x;
+        if (ppuY > 0)
+            b.y = minSize.y;
+        best = b;
+    }
+    else
+        return wxWindow::DoGetBestSize();
+
+    // Add any difference between size and client size
+    wxSize diff = GetSize() - GetClientSize();
+    best.x += wxMax(0, diff.x);
+    best.y += wxMax(0, diff.y);
+
+    return best;
+}
+
 void wxGenericScrolledWindow::OnPaint(wxPaintEvent& event)
 {
     // the user code didn't really draw the window if we got here, so set this
diff --git a/src/generic/splitter.cpp b/src/generic/splitter.cpp
index d39356302c..0c04fde000 100644
--- a/src/generic/splitter.cpp
+++ b/src/generic/splitter.cpp
@@ -122,6 +122,7 @@ void wxSplitterWindow::Init()
     m_firstY = 0;
     m_sashPosition = m_requestedSashPosition = 0;
     m_sashGravity = 0.0;
+    m_sashSize = -1; // -1 means use the native sash size
     m_lastSize = wxSize(0,0);
     m_checkRequestedSashPosition = false;
     m_minimumPaneSize = 0;
@@ -471,7 +472,7 @@ bool wxSplitterWindow::SashHitTest(int x, int y, int tolerance)
 
 int wxSplitterWindow::GetSashSize() const
 {
-    return wxRendererNative::Get().GetSplitterParams(this).widthSash;
+    return m_sashSize > -1 ? m_sashSize : wxRendererNative::Get().GetSplitterParams(this).widthSash;
 }
 
 int wxSplitterWindow::GetBorderSize() const
diff --git a/src/gtk/scrolwin.cpp b/src/gtk/scrolwin.cpp
index df01919089..484aa18183 100644
--- a/src/gtk/scrolwin.cpp
+++ b/src/gtk/scrolwin.cpp
@@ -329,6 +329,60 @@ void wxScrolledWindow::DoSetVirtualSize( int x, int y )
         Layout();
 }
 
+// wxWindow's GetBestVirtualSize returns the actual window size,
+// whereas we want to return the virtual size
+wxSize wxScrolledWindow::GetBestVirtualSize() const
+{
+    wxSize  clientSize( GetClientSize() );
+    if (GetSizer())
+    {
+        wxSize minSize( GetSizer()->CalcMin() );
+
+        return wxSize( wxMax( clientSize.x, minSize.x ), wxMax( clientSize.y, minSize.y ) );
+    }
+    else
+        return clientSize;
+}
+
+// return the size best suited for the current window
+// (this isn't a virtual size, this is a sensible size for the window)
+wxSize wxScrolledWindow::DoGetBestSize() const
+{
+    wxSize best;
+
+    if ( GetSizer() )
+    {
+        wxSize b = GetSizer()->GetMinSize();
+
+        // Only use the content to set the window size in the direction
+        // where there's no scrolling; otherwise we're going to get a huge
+        // window in the direction in which scrolling is enabled
+        int ppuX, ppuY;
+        GetScrollPixelsPerUnit(& ppuX, & ppuY);
+
+        wxSize minSize;
+        if ( GetMinSize().IsFullySpecified() )
+            minSize = GetMinSize();
+        else
+            minSize = GetSize();
+
+        if (ppuX > 0)
+            b.x = minSize.x;
+        if (ppuY > 0)
+            b.y = minSize.y;
+        best = b;
+    }
+    else
+        return wxWindow::DoGetBestSize();
+
+    // Add any difference between size and client size
+    wxSize diff = GetSize() - GetClientSize();
+    best.x += wxMax(0, diff.x);
+    best.y += wxMax(0, diff.y);
+
+    return best;
+}
+
 /*
  * pixelsPerUnitX/pixelsPerUnitY: number of pixels per unit (e.g. pixels per text line)
  * noUnitsX/noUnitsY:        : no. units per scrollbar
diff --git a/src/gtk1/scrolwin.cpp b/src/gtk1/scrolwin.cpp
index df01919089..484aa18183 100644
--- a/src/gtk1/scrolwin.cpp
+++ b/src/gtk1/scrolwin.cpp
@@ -329,6 +329,60 @@ void wxScrolledWindow::DoSetVirtualSize( int x, int y )
         Layout();
 }
 
+// wxWindow's GetBestVirtualSize returns the actual window size,
+// whereas we want to return the virtual size
+wxSize wxScrolledWindow::GetBestVirtualSize() const
+{
+    wxSize  clientSize( GetClientSize() );
+    if (GetSizer())
+    {
+        wxSize minSize( GetSizer()->CalcMin() );
+
+        return wxSize( wxMax( clientSize.x, minSize.x ), wxMax( clientSize.y, minSize.y ) );
+    }
+    else
+        return clientSize;
+}
+
+// return the size best suited for the current window
+// (this isn't a virtual size, this is a sensible size for the window)
+wxSize wxScrolledWindow::DoGetBestSize() const
+{
+    wxSize best;
+
+    if ( GetSizer() )
+    {
+        wxSize b = GetSizer()->GetMinSize();
+
+        // Only use the content to set the window size in the direction
+        // where there's no scrolling; otherwise we're going to get a huge
+        // window in the direction in which scrolling is enabled
+        int ppuX, ppuY;
+        GetScrollPixelsPerUnit(& ppuX, & ppuY);
+
+        wxSize minSize;
+        if ( GetMinSize().IsFullySpecified() )
+            minSize = GetMinSize();
+        else
+            minSize = GetSize();
+
+        if (ppuX > 0)
+            b.x = minSize.x;
+        if (ppuY > 0)
+            b.y = minSize.y;
+        best = b;
+    }
+    else
+        return wxWindow::DoGetBestSize();
+
+    // Add any difference between size and client size
+    wxSize diff = GetSize() - GetClientSize();
+    best.x += wxMax(0, diff.x);
+    best.y += wxMax(0, diff.y);
+
+    return best;
+}
+
 /*
  * pixelsPerUnitX/pixelsPerUnitY: number of pixels per unit (e.g. pixels per text line)
  * noUnitsX/noUnitsY:        : no. units per scrollbar