I have the same problem since few days. The only way that i have solved the problem was disabling antivirus service and requeue the emials. After that i enabled again and the server continues working without problem during 2 or 3 day.After that i got the same problem again. In the logs i can see the following error message:
Jul 30 11:59:46 radal amavis: (13677-04-9) (!!) TROUBLE in check_mail: spam_scan FAILED: timed out
Jul 30 11:59:46 radal amavis: (13677-04-9) (!) PRESERVING EVIDENCE in /opt/zimbra/amavisd/tmp/amavis-20080730T115010-13677
S.O.:Red Hat Enterprise Linux ES release 4 (Nahant Update 6)
Zimbra: Release 4.0.2_GA_362.RHEL4_64_20060922142700 RHEL4_64 FOSS edition
QUOTE=tbullock;26201]It is related to Anti-virus/SpamAssassin. I am not sure what exactly the problem is, but when I disable he service mail is handled normally.
I am hoping the problem will go away once I upgrade to FC5 and 4.0.2, whenever that happens...lol..
I do seem to remember running a "yum" probably around the same time this happened. I have not changed any passwords.
Anyone have any thoughts?[/QUOTE]