I have worked quite a bit with CentOS 4.x with SAN, multipathing, LVM etc. The way I mount my file systems is using a script that is called during startup that runs fsck, imports the physical volumes, and volume groups, activates the logical volumes, creates the mount point if needed then mounts the volume, I mainly made it for software iSCSI due to the iscsi stack loading after the system mount process. I adapted it to my fiber channel systems as well and it worked great(mainly so I could have a consistent experience between FC and iSCSI).
In testing with CentOS 5.1 it seems that my entries in /etc/fstab that are marked "noauto" are still infact queried when the system boots (before multipathing, etc fires up). These devices don't exist at the time which causes the boot to halt(so I can fsck the file system manually). I have worked around it by commenting out the line in fstab, and just adjusting my script to look for the commented line, but this never happened under CentOS 4.x, seems like a bug ? I peeked at Red Hat's bugzilla but didn't see much.
If so I can file one..
thanks
nate