Mailscanner suddenly started taking up 100% of available memory

[Andrew Hoying]

Yesterday morning, for the first time, mailscanner began consuming several
hundred megabytes of memory every hour until the system ran out of memory
and killed mailscanner. The process would then repeat every 4 hours or so.
Regardless of the fact that I should have resource limits in place to
prevent mailscanner from using all the memory, I've never seen this behavior
before. I've been running mailscanner on this server since October of last
year without any similar problems. I am currently running version  3.13-2.
The only thing that changed, and I'm pretty sure that this is the culprit,
is that mcafee auto-updated to dat version 4197 on Wednesday. I'm not sure
where to begin troubleshooting this particular problem, and certainly am
open to suggestions.

Thank you,
Andrew