Now we've got the same problem at the second customersite, and I have no
idea, how to solve it:

After 2-3 weeks of uptime, the server has a standard cpu utilization of
min 40%, up to 60%, without anyone doing anything on the server.

HW/SW which are identical on both sites:
- HP Probliant DL380G4, Xeon 3.4 GHz, with 2 GB RAM, and write back cache
- OES (NW) with all patches up to 3-4 weeks ago
- BackupExec 9.1
- Symantec AV 9.01
- NIC bundling active with the HP tools/drivers

When the server is rebooted, everything works fine, for 2-3 weeks.

any hint, how to find out, where the bug is?