linuxhelp
The immediate answer is to select the old kernel at start up.
It's a bad idea generally speaking to use unsupported hardware that requires custom mods to the kernel. You overlook the fact that by not upgrading your kernel, you will not get any security updates & fixes and newer hardware support etc etc.
It's relatively easy to select hardware that is supported by the underlying OS, ie CentOS 4.8 for sme7.4, or as cactus suggests do away with your RAID card & use software RAID. Unless you are using very big drives ie 2Tb plus, you probably won't notice any performance difference.