If the encryption is so horrible why is there any support (with bad performance) at all in Python?
It would be better to remove it altogether.
This prevents users from building software using this feature only to find out later how bad the performance is. (This is the main reason why I have submitted this patch.)
If the support had not been in Python I would not have used this feature to begin with.

To reiterate my previous point. Either support something and do it well, or don't. Don't do a half job.

Please note that there are more attempts to fix this, so I am not completely alone here.
http://pypi.python.org/pypi/czipfile