dlw63
If you bothered to do a search on procmail, you would have found this thread which probably answers your query. Learn to use the search function.
There are some suggestions in the thread that may resolve your issue.
The simple answer is that procmail only works for local delivery, so if you use the "forward to" setting unders users, then the message does not get filtered by procmail. This then stops spam messages being put in your Junkmail folder.
Spamassassin is still working ie tagging the messages, but just not moving them to the junkmail folder.
Unless you were using a spam filter contrib under sme 5.6 that did not use procmail, you would have had the same problem.
See:
http://forums.contribs.org/index.php?topic=25568.0