You must use the correct HBA device driver and firmware levels for the Apple hosts that are running on the Mac OS X server v10.5.x operating system.
For more information about ATTO HBA, device driver, and firmware downloads, go to the following website:
http://attotech.com/solutions/IBM/
After you log in to the support pages, select Celerity xxx for IBM SAN Volume Controller, where xxx is your HBA type.