--- /System/Library/Frameworks/Python.framework/Versions/Current//lib/python2.7/argparse.py	2014-09-17 18:56:24.000000000 +0400
+++ argparse.py	2014-09-17 19:26:33.000000000 +0400
@@ -2089,7 +2089,7 @@
                 return None
 
         # if it contains a space, it was meant to be a positional
-        if ' ' in arg_string:
+        if ' ' in arg_string and arg_string[0] not in self.prefix_chars:
             return None
 
         # it was meant to be an optional but there is no such option