Sony TRV480 not detected firewire Windows XP or Vista

Hi Friends,
I recently bought a Sony handycam TRV480 which is rated high for
transferring contents from Hi8 and H8 tapes to PC through firewire. However,
neigther my XP MCE laptop nor my Vista Ultimate desktop detect the camcorder.

The camcorder displays "DV in" when connected through firewire to
both machines. Both machines are able to import content (using Moive Maker)
from another mini DV camcorder over firewire. Hence I know that the firewire
interface is working on both machines.

Do I need a drivers for this camcorder for XP or Vista? Do I need to
do any special set up on the camcorder? I couldn't find the info. on Sony's
support site.

I would appreciate if any of you have solution(s) for this problem.

Thanks