I have the new aacraid driver working on my system now.  The patch is
against the 2.5.66 updates that you gave me.  I made the following
changes:

aachba.c aac_scsi_cmd()
There was a race accessing the scsicmd pointer accessing the host_lock.
I made a local pointer to the Scsi_Host so the spin_lock_irq after
aac_read wouldn't panic.  I think that sometimes the I/O would be done
and the memory freed before returning invalidating the scsicmd pointer.
I made the same change in aac_io_done in case scsi_done had freed the
scsicmd memory before returning.

comminit.c aac_alloc_comm()
AdapterFibsVirtualAddress was set to the virtual address of base.  I
changed it to set it to the phys address.  I compared this to code
pointed to by matt domsch on the aacraid devel list on the 5th.  Its
aac_alloc_comm sets this variable to the phys address.  This fixed the
probelem where the entry->addr was bad.  Another was to fix it I guess
would be to leave this change alone and not try to convert the address
in aac_command_normal.

dpcsup.c aac_response_normal()
Changed the bus_to_virt to the calculation we talked about last month.
dpcsup.c aac_command_normal()
Changed the bus_to_virt to the calculation.