I think you can use the slipstream cd that are on this forum. On the first look the Pi2515 use the same drivers.
(Same Sata, audio, lan and wireless drivers.)
For the other drivers like video i can't help you.viewtopic.php?f=90&t=30189
([Pi 2530] Windows Xp Pro Retail install cd)
If you try it let me know if it worked. I can't test it.
If it work other people can be helped to.