Thanks for the extra test cases. Assuming they should all fail, here's my new test stub. Looks good to me. Review and comment appreciated. http://www.pccc.com/downloads/MIMEDefang/contrib/check_primary_mx_stub.pl Regards, KAM > If you need some test cases: > zqy152214 at liyuanculture.com > formation2005 at carmail.com > chaifai at flashmail.net