vista x64, should be the same. This might be part of canons plan to make poeple upgrade, i've a scanner that they did not support in 64bit that 64 bit is 'unstable' not unstable enough for lots of other of thier products to have 64bits drivers.
What are you trying to do, such that you want to connect it? use a card reader for downloading photos. Create a VMware 32bit installation for other reasons? or install XP mode, google it, or look on the MS website?