diff -r 25fd9aeeff91 Lib/idlelib/configHandler.py
--- a/Lib/idlelib/configHandler.py	Thu Jun 12 01:03:08 2014 -0400
+++ b/Lib/idlelib/configHandler.py	Thu Jun 12 16:28:40 2014 +0530
@@ -19,6 +19,7 @@
 """
 import os
 import sys
+import re
 
 from configparser import ConfigParser, NoOptionError, NoSectionError
 
@@ -526,14 +527,21 @@
     def GetCurrentKeySet(self):
         result = self.GetKeySet(self.CurrentKeys())
 
-        if sys.platform == "darwin":
-            # OS X Tk variants do not support the "Alt" keyboard modifier.
-            # So replace all keybingings that use "Alt" with ones that
-            # use the "Option" keyboard modifier.
-            # TO DO: the "Option" modifier does not work properly for
-            #        Cocoa Tk and XQuartz Tk so we should not use it
-            #        in default OS X KeySets.
-            for k, v in result.items():
+        def replace(m):
+            return m.group('prefix') + m.group('alpha').swapcase()+'>'
+
+        pat = '(?P<prefix><[A-Za-z-]+Key-)(?P<alpha>[a-zA-Z])>'
+        for k, v in result.items():
+            v2 = [re.sub(pat, replace, x) for x in v]
+            if v != v2:
+                v.extend(v2)
+            if sys.platform == "darwin":
+                # OS X Tk variants do not support the "Alt" keyboard modifier.
+                # So replace all keybingings that use "Alt" with ones that
+                # use the "Option" keyboard modifier.
+                # TO DO: the "Option" modifier does not work properly for
+                #        Cocoa Tk and XQuartz Tk so we should not use it
+                #        in default OS X KeySets.
                 v2 = [ x.replace('<Alt-', '<Option-') for x in v ]
                 if v != v2:
                     result[k] = v2