[Mimedefang] Error message:Problem running virus scanner: code=2

[Mathew Thomas]

Dear All,

We have got four mail gateways runninng Solaris 9 with
Sendmail 8-13.1 
Mimedefang 2.44 
SpamAssassin 2.64 +Razor 2.61 + DCC 1.2.50 
Clamav 0.75.1  
 Uvscan 4.3.20

There were thousands of following error message yesterday. The above
version/set have been running  for the last 2 years without any problem.
It happened for an hour and looks like it is ok now and there is no
error message now.

Dec  7 06:00:03 its-mu-mail3.its.rmit.edu.au mimedefang.pl[27407]: [ID
702911 mail.warning] Problem running virus scanner: code=2,
category=swerr, action=tempfail
Dec  7 06:00:03 its-mu-mail3.its.rmit.edu.au sendmail[14048]: [ID
801593 mail.info] jB6J01ZS014048: from=<ikrxhohbo995 at yahoo.com>,
size=3525, class=0, nrcpts=1,
msgid=<04jlr$$2hk-2j9n30ujn-7a7-1 at pb0h99w.x3sc>, bodytype=8BITMIME,
proto=SMTP, daemon=MTA, relay=[59.17.124.244]
Dec  7 06:00:03 its-mu-mail3.its.rmit.edu.au mimedefang.pl[27407]: [ID
702911 mail.debug] filter: jB6J01ZS014048:  tempfail=1
Dec  7 06:00:03 its-mu-mail3.its.rmit.edu.au mimedefang[292]: [ID
210624 mail.debug] jB6J01ZS014048: Tempfailing because filter instructed
us to
Dec  7 06:00:03 its-mu-mail3.its.rmit.edu.au sendmail[14048]: [ID
801593 mail.info] jB6J01ZS014048: to=<norchis at cs.rmit.edu.au>,
delay=00:00:01, pri=33525, stat=Problem running virus-scanner


What would be the problem ? What should I do to fix it.

Thanks
Mathew