FreeBSD 4.8 and instabilities with Buslogic SCSI drivers in VMWare

[denon]

We've been doing more work with VMware and FreeBSD lately. Overall it's 
been going well, but we have a machine that's giving me grief, and I'm a 
bit concerned.

It's running 4.8-Release, with a single virtual SCSI drive.  It's been 
running fine for months, but as of recently, it's started locking up.  When 
it locks up, this is what's in the messages:
/kernel: (da0:bt0:0:0:0): CCB 0xca993340 - timed out
/kernel: bt0: btdone - Attempt to free non-active BCCB 0xca9933c0

This is the scsi card it sees (from vmware)
/kernel: bt0: <Buslogic Multi-Master SCSI Host Adapter> port 0x1060-0x107f 
mem 0xfd000000-0xfd00001f irq 9

The host machine is running Windows 2003 Server, on an SMP Xeon host.  The 
virtual machine's I/O is pretty minor, and it doesn't hit the cpu/etc much 
either. Pretty lightweight install.

Any thoughts on the situation would be appreciated.

-d