From what I can tell (doing web searches) the advansys scsi drivers are no longer considered stable--one has to rebuild the kernel/modules using "broken" drivers, which I won't do because I like keeping things stock (and yum updatable). There are workarounds, like the dkms stuff, but having used early versions of dkms for our nvidia cards, I'm very gun shy of dkms--lots of problems with it, at least for me.
Sure caught me by suprise. It's unusual (in my limited experience) to see kernel level support move backwards in this manner. What was advansys thinking when they dropped the ball on kernel 2.6? (rhetorical question).
"Thanks" adaptec for staying on top of things. I had enough spare adaptecs to sort things out.
FC2 is working out very well for us (two days of testing and things are great).
--- John