Tagging everything as spam

[Joe Stuart]

Out of nowhere last night my server running Mailscanner and spamassassin
started tagging everything as spam.  No matter what spamassassin scores
the message it tags it as spam.  I've checked my required scores and the
low and high are set at 5 and 10, so thats not the problem and I cant
find anything unusual in my log files. Does anyone have any thoghts as
to what may be causing this? There was also nobody doing any work on the
server this weekend.

Thanks