An older version of Cookie.py that I used in Mailman
allowed : (colon) in the keys.  The version that's in
Python right now does not.  The question comes down to
whether Cookie.py should be a strict interpretation of
RFCs 2109 and 2068 (which appears to mandate such keys
be enclosed in quotes) or a looser interpretation.  

On the one hand, it shouldn't allow you to break the
standards, but OTOH most browsers allow this, and
besides, it's entirely possible that you'll get
ill-conformant cookie data.  Be liberal in what you
accept and strict in what you generate.

Here's the thread in python-dev:

http://mail.python.org/pipermail/python-dev/2001-October/017722.html

Mostly I'm submitting this bug so it doesn't get buried
in my inbox.  Posted patch is attached.

Logged In: YES 
user_id=3066

This looks good to me.  Please check it in and close the bug.

Logged In: YES 
user_id=12800

I've decided to reject and close this for Python 2.2.  I'm
not comfortable with making this change so late in the beta
cycle.

(I've worked around this in Mailman so it isn't of immediate
import to me now.)