What to do if new HD doesn't show up in /dev

[John G. Heim]

My department put a new disk in one of our servers. The machine has a RAID 
controller with 4 disks and then this new disk is attached to one of the 
sata ports. There used to be a 80 Gb disk attached there and the new disk 
that we just replaced it with is 1 Tb (1000 Gb).

Anyway, the old 80 Gb drive used to be seen as sdb. But the new drive 
doesn't show up at all. If I run 'sfdisk -l', the RAID disks show up as sda. 
But there is no sdb.

I was using the stock debian kernel in lenny. But I also tried the 2.6.28 
kernel from the debian kernel team's experimental archive. Still no 
/dev/sdb.

What else can I try?