I have two wd400jb's which i have had in raid 0 for ages with XP installed on them. I tried to do this with linux to see if there would be much of a notable difference. I entered the raid controller's bios and striped them (actually done it on two different controllers, one being serial ata and the other normal ide) but when it comes to partitioning with disk druid in the installation it detects the hard drives as being seperate?!?! Could this be due to linux not having correct drivers for the controller? I'm sure they were setup in stripe config correctly....
Has anyone else had this problem? Cheers

Yes, it's that linux does not have the correct driver. Look for a linux driver disk for your controller. I had this on a server I recently set up, and the correct DD fixed the problem.