diff --git a/distrib/msw/tmake/gtk.t b/distrib/msw/tmake/gtk.t
index 5bdc9e97ca..8e87b60025 100644
--- a/distrib/msw/tmake/gtk.t
+++ b/distrib/msw/tmake/gtk.t
@@ -67,6 +67,8 @@
     
     #! find all our headers
     foreach $file (sort keys %wxWXINCLUDE) {
+        next if $wxWXINCLUDE{$file} =~ /\bR\b/;
+
         $project{"GTK_HEADERS"} .= $file . " "
     }
 
diff --git a/distrib/msw/tmake/motif.t b/distrib/msw/tmake/motif.t
index 95c6f3a391..d67e487cdf 100644
--- a/distrib/msw/tmake/motif.t
+++ b/distrib/msw/tmake/motif.t
@@ -67,6 +67,8 @@
     }
     #! find all our headers
     foreach $file (sort keys %wxWXINCLUDE) {
+        next if $wxWXINCLUDE{$file} =~ /\bX\b/;
+
         $project{"MOTIF_HEADERS"} .= $file . " "
     }
 
diff --git a/distrib/msw/tmake/os2.t b/distrib/msw/tmake/os2.t
index a6f11a4a16..65a07b0352 100644
--- a/distrib/msw/tmake/os2.t
+++ b/distrib/msw/tmake/os2.t
@@ -58,6 +58,8 @@
     }
     #! find all our headers
     foreach $file (sort keys %wxWXINCLUDE) {
+        next if $wxWXINCLUDE{$file} =~ /\bP\b/;
+
         $project{"OS2PM_HEADERS"} .= $file . " "
     }