[CentOS] Automatically detecting LUNs without a reboot

  Hi everybody.

I have an HP StorageWorks array connected to one of my servers, 
connected via an LSI controller (lspci reports: SCSI storage controller: 
LSI Logic / Symbios Logic SAS1068E PCI-Express Fusion-MPT SAS (rev 08)) 
on an HP DL385 running CentOS 5.5 x86_64.

I have set up multipath and all is working but, when I create a snaphost 
and export it as a new LUN from the HP web interface, it does not appear 
as  a new disk. If I reboot, I get the LUN to appear as a new SCSI 
device (sd[a-z]).

Is there any way I can force automatic detection? One of the reasons to 
use snapshots is to be able to back up the system without downtime, so 
not being able to detect the LUNs makes the whole set up a bit pointless.

I have tried kudzu, the rescan-scsi-bus.sh script and everything else I 
have found online, with no luck. The LSI tools only seem to be available 
for i386, and I would like to avoid adding the 32bit environment, if I can.

Any help would be greatly appreciated.

Thanks,

Gabriel Tabares