yeah dont do it that way :/ debians own kernel is much better and tweaked to work :/
take a look here why -->
http://www.linuxquestions.org/questi...d.php?t=481259
i suggest try to install the 2.6 kernel with the package system.
if ya realy want to compile it yourself to tweak it further i suggest you go with a slackware distro or maybe arch or something. they are more open to a self compiled kernel.
and the real answer:
you gotta look into your device support and find the sata support and add it to the kernel since you use a sata drive (sda - right? correct me if im wrong) (and raid 1 support must be on ofcourse^^) ill post back if im home with a more detailed explenation if ya need it.