diff -r c5e2ea9e3aa7 Lib/idlelib/aboutDialog.py
--- a/Lib/idlelib/aboutDialog.py	Mon Apr 08 00:26:43 2013 +0200
+++ b/Lib/idlelib/aboutDialog.py	Sun Apr 07 23:38:47 2013 -0400
@@ -66,12 +66,7 @@
         labelPythonVer = Label(frameBg, text='Python version:  ' + \
                                sys.version.split()[0], fg=self.fg, bg=self.bg)
         labelPythonVer.grid(row=9, column=0, sticky=W, padx=10, pady=0)
-        # handle weird tk version num in windoze python >= 1.6 (?!?)
-        tkVer = repr(TkVersion).split('.')
-        tkVer[len(tkVer)-1] = str('%.3g' % (float('.'+tkVer[len(tkVer)-1])))[2:]
-        if tkVer[len(tkVer)-1] == '':
-            tkVer[len(tkVer)-1] = '0'
-        tkVer = '.'.join(tkVer)
+        tkVer = self.tk.call('info', 'patchlevel')
         labelTkVer = Label(frameBg, text='Tk version:  '+
                            tkVer, fg=self.fg, bg=self.bg)
         labelTkVer.grid(row=9, column=1, sticky=W, padx=2, pady=0)