FYI... I ran a blanket yum update on the server this evening. A lot of things had fallen behind.
I also upped our spam protection a little bit. I added an RBL server (see http://en.wikipedia.org/wiki/DNSBL) to front-end qmail. Hopefully that will take some of the burden off of spamassassin and free up some resources.
Let me know if you notice anything that isn't working anymore.