Hi NetBSD Help!

I have a new Dell PowerEdge 2650 on which I'm trying to install NetBSD. 
The installation script fails to find drives.  I have tried the
installation boot cd from NetBSD 1.6.1, NetBSD with KAME 1.6.1, NetBSD
1.6.2 and NetBSD with KAME 1.6.2.

The SCSI controller is a standard Adaptec AIC-7899, and the BIOS 
SCSI Select utility sees the drives just fine in hardware.

During load of the installation kernel, I do not see any references to
scsibus, or sd drives.

OpenBSD 3.4 installs okay on this machine, and indicates there is a Dell
PERC 3/Di.  I'm not certain what that refers to, but it seems to play a
role in the driver implementation, judging by the web searches I have
done on this problem.

Suggestions welcome - let me know if I need to provide any more details
regarding my setup.

Thanks!

Nancy Davis