Time Machine wont open on Xserve Leopard 10.5.7

Hi
I have a new Xerve running 2 1tb drives set up as mirrored raid (screenshot attached) and im backing up using a 2 tb MyBook External harddrive with Time Machine, my problem is, when i click to go into time machine, all that happens is that the desktop opens as a window twice, then i have to click the close button of one of those windows, then the dock goes down and up, then im back to normal, maybe i shouldnt be pointing time machine at my raid set, but theres nothing else on there to point it to.
Anyone got any ideas?

b.t.w. im getting no error messages and the data appears to be on the mybook