CentOS - Nov 2006 - onboard adaptec SAS RAID controller not seeing drive(s)

I have a Supermicro SuperServer 6025B-3V with their X7DB3 mobo.  It
has an onboard Adaptec SAS RAID controller and has been configured
as a RAID1 with two Seagate Cheetah 15k.4 disks.  Original attempts at
installing  CentOS4.4  x86_64 appeared to load the aic94xx driver, but then
reported something like "No hard drives found...".  I grabbed the
x86_64
aacraid driver disk from Adaptec (updated 23 OCT 2006) and tried a
"linux dd" install.  Although the driver disk appears to load, I still
get the
"No hard drives found.." message.

I'm waiting for a response from Supermicro, but any advice from this list
(including a controller that works) would be greatly appreciated.

Thanks,
Steve Finley