I'd buy a newer adaptec SCSI controller that supports Server 2003. Guessing that your controller is an older one being that it is paired up with four 9.1GB SCSI drives. If you dont need anything but RAID 0 or RAID 1, you can get a cheap Adaptec controller, but if you need RAID 5, that will cost more.
This would not be the first device I have seen not quite compatible with Server 2003. I had some older NICs that didnt work quite right as well as an older SATA controller.