Index: extconf.rb
===================================================================
--- extconf.rb	(revision 27020)
+++ extconf.rb	(working copy)
@@ -999,7 +999,7 @@
   end
 
   if TkConfig_Info['TK_INCLUDE_SPEC'] && 
-      have_tk_h = try_cpp('tk.h', TclConfig_Info['TK_INCLUDE_SPEC'])
+      have_tk_h = try_cpp('tk.h', TkConfig_Info['TK_INCLUDE_SPEC'])
     $INCFLAGS << " " << TkConfig_Info['TK_INCLUDE_SPEC']
   elsif have_tk_h = have_header('tk.h')
     # find
@@ -1026,12 +1026,12 @@
   if File.exist?(dir = File.join(TkLib_Config["tcltk-framework"], 
                                  'Tcl.framework', 'Headers'))
     TclConfig_Info['TCL_INCLUDE_SPEC'] = "-I#{dir} "
-    TclConfig_Info['TK_INCLUDE_SPEC'] = "-I#{File.join(TkLib_Config['tcltk-framework'], 'Tk.framework', 'Headers')} "
+    TkConfig_Info['TK_INCLUDE_SPEC'] = "-I#{File.join(TkLib_Config['tcltk-framework'], 'Tk.framework', 'Headers')} "
   else
     dir = Dir.glob(File.join(TkLib_Config["tcltk-framework"], 
                              'Tcl.framework', '*', 'Headers'))
     TclConfig_Info['TCL_INCLUDE_SPEC'] = "-I#{dir[0]} " unless dir.empty?
-    TclConfig_Info['TK_INCLUDE_SPEC'] = "-I#{Dir.glob(File.join(TkLib_Config['tcltk-framework'], 'Tk.framework', '*', 'Headers'))[0]} "
+    TkConfig_Info['TK_INCLUDE_SPEC'] = "-I#{Dir.glob(File.join(TkLib_Config['tcltk-framework'], 'Tk.framework', '*', 'Headers'))[0]} "
   end
 
   $LDFLAGS << ' -framework Tk -framework Tcl'
@@ -1384,8 +1384,13 @@
 
 # search X libraries
 use_X = search_X_libraries
+if use_X
+  if TkConfig_Info['TK_XINCLUDES'] &&
+    !TkConfig_Info['TK_XINCLUDES'].strip.empty?
+    $INCFLAGS << " " << TkConfig_Info['TK_XINCLUDES'].strip
+  end
+end
 
-
 #---------------------------------------------------
 
 if (TkLib_Config["tcltk-framework"] ||