What is the exact build of avast! you have installed?
Could you send us the minidumps corresponding to the crashes? I guess Vlk and/or Lukor would like to see them.
I’m having the same problem on my Windows 2003 Server (after paying Microsoft £200 to analyze the crash dump). I notice on this page the version dated December 2, 2004 states a fix for this problem, but the latest Server version of Avast is from November.
Would it be possible to replace the offending file with one from one of our workstations’ Pro installs?