If you get false positives due to FORGED_MUA_OUTLOOK hits, here are some fixes (pick one) for the admin to implement to solve this problem:
 *upgrade to the newest version of SpamAssassin (better solution) 
 *edit the line in the file 50_scores.cf, replacing the #s with smaller #s (e.g. 0 or 1).

This [[http://bugzilla.spamassassin.org/show_bug.cgi?id=4065|already-fixed bug]] happens because a new version of Outlook wasn't recognized by the rules of the old SpamAssassin installation used on your mail.