Hi,
of course we're are currently in the process of getting this thing to a linux box with apache. We'll see what will happen.

The sad side of this is: the error is not reproducible. It occurred once during a nightly stress-test. We set up another server (w/o any other software) and that machine is running just fine. The first box also run some virus scanning software as well as backups. Rather complicated environment :-(

I am not hoping for a code analysis here, just a pointer where the problem may be lurking.