XP Wont install

Hi, I have Vista pre installed on my HP Pavilion dv2000 and was hoping to get a dual boot with XP. I have partitioned the HDD as you suggested and that worked ok, I now find that when atempting to install XP the screen says that it has compatibility issues as the current version is a later version.
how can I get around this. I have XP SP2.

Thanks
James