>>> from urllib2 import urlopen
>>> a = urlopen('http://www.voidspace.org.uk')
>>> i = a.info()
>>> for entry in i: print entry
Traceback (most recent call last):
  File "<pyshell#11>", line 1, in -toplevel-
    for entry in i: print entry
  File "D:\PYTHON23\lib\rfc822.py", line 390, in 
__getitem__
    return self.dict[name.lower()]
AttributeError: 'int' object has no attribute 'lower'

Iterating over an rfc822 message (above done from 
urllib2) causes an exception. Could be fixed by returning 
an iter(self.dict) from the __iter__ method.

This bug looks similar to bug 1017329.