Weird assertion in win2k3 checked build

Hi,
As many of the expert in this news group recommended, I had the QA engineers
dedicate one machine for checking my driver in a checked build of win2k3.
My driver is upperfilter to class volume.
An assertion appeared in windbg after the QA played with external storage
(Plugging/Unplugging it several times):
*** Assertion failed: SRB_STATUS(Srb->SrbStatus) != SRB_STATUS_PENDING
*** Source File: d:\srv03rtm\drivers\storage\classpnp\class.c, line 3034

I checked the code, and it seems that someone in the disk stack (Probably
the HBA itself) is misbehaving.
Can someone shed some light here? As far as I can see, the lower driver has
completed an SRB without changing it status.

Thanks,
Eran.