diff -r c27527dce71e Lib/argparse.py
--- a/Lib/argparse.py	Sun Sep 01 10:22:41 2013 +0200
+++ b/Lib/argparse.py	Mon Sep 02 00:09:01 2013 +0300
@@ -511,10 +511,13 @@
         # if there was help for the action, add lines of help text
         if action.help:
             help_text = self._expand_help(action)
-            help_lines = self._split_lines(help_text, help_width)
-            parts.append('%*s%s\n' % (indent_first, '', help_lines[0]))
-            for line in help_lines[1:]:
-                parts.append('%*s%s\n' % (help_position, '', line))
+                    
+            # only if can be informative. otherwise fail silently
+            if help_width > 0:
+                help_lines = self._split_lines(help_text, help_width)
+                parts.append('%*s%s\n' % (indent_first, '', help_lines[0]))
+                for line in help_lines[1:]:
+                    parts.append('%*s%s\n' % (help_position, '', line))
 
         # or add a newline if the description doesn't end with one
         elif not action_header.endswith('\n'):