Once again, and I'm not holding out much hope... The ones that ship with 10.6 MAY be capable of booting into 10.5.
You'll have to go to the store with a generic, retail 10.5 disc and experiment, but it would certainly be worth your while to try; you have absolutely nothing to lose.
Edit: I suggest trying with a 10.5.8 disc or bootable clone if possible.
Last edited by artie505; 03/20/10 07:52 AM.