Index: Lib/webbrowser.py
===================================================================
--- Lib/webbrowser.py	(revision 68118)
+++ Lib/webbrowser.py	(working copy)
@@ -103,10 +103,11 @@
 
 if sys.platform[:3] == "win":
     def _isexecutable(cmd):
+        win_exts = (".exe", ".com", ".bat", ".cmd")
         cmd = cmd.lower()
-        if os.path.isfile(cmd) and cmd.endswith((".exe", ".bat")):
+        if os.path.isfile(cmd) and cmd.endswith(win_exts):
             return True
-        for ext in ".exe", ".bat":
+        for ext in win_exts:
             if os.path.isfile(cmd + ext):
                 return True
         return False