iCal Server and Python causing max CPU usage on 10.5.1 server

We are having an issue with iCal Server where a python process is monopolizing the CPU (70%-95%) to the point everything grinds to a halt. Once iCal is stopped, then started again it will be ok for anywhere from 10 minutes to a few hours before it starts all over again. caldavd error Log is being bombarded with what looks like every transaction. See example below: 2008-01-07 11:26:46-0600 [-] [caldav-8008] [HTTPChannel,4634,192.168.1.139] PROPFIND /principals/__uids__/BA237A85-F880-4A89-B1C1-F07E72A1508E/ HTTP/1.1 This may be completely unrelated, but the DirectoryService process seems to be running high (35%-40%) as well. Any help would be greatly appreciated! Fun Facts: G5 Xserve - Dual 2.0 4GB RAM Mac OS 10.5.1 Server DNS seems to be in working order