10.4.11: AppleFileServer Hogging CPU on my Server – causing big problems

I have a server (G5 1.8gHz duals, max RAM) that hosts a number of Apple/Windows sharepoints as well as the home directories for 35 Open Directory users. The files live on an attached external SATA RAID array. While I installed the .11 update a couple weeks ago - this problem began today... My mobile OD users are fine in terms of computer speeds but non-mobile users are experiencing massive slowdowns (typing lags by a few seconds even). On the server, I see that the AppleFileServer is running between 90-120% of the CPU in top, but is only using about 20mb of RAM. It is hogging the processor and hurting our system. I have read all the AFP Tuning articles here and have already implemented a few ideas to no avail. While I know that I can switch them all to Mobility mode, that isn't possible for me here as users need to log-in from many different stations during the day. I have restarted the server, repaired permissions, etc. but the AppleFileServer continues to slam the processor. Prior to today, it would run something about 20%-70%. Any help would be immensely appreciated!