Airport Express with XP 64 bit

I am about to dive into PC Audio. Right now I have my music library in iTunes on an old Sony Vaio, running XP "home version," I think. I have acquired an old work laptop that has much better specs in the processor and RAM, but it has XP 64. Are there any issues anyone knows about running AirTunes to an AE from XP 64?
Signal path is this: xp 64 bit laptop-->AirTunes pushing AIFF or ALC-->Airport Express-->mini-Toslink-->BurrBrown 24/96 DACs on a Denon 3310-->Rotel RB-1080-->B&W 685s, I also run a HSU sub from the Denon. All interconnects are AQ G-snakes, speaker wire is AQ type-4, sub cable is Sub-X.
Sometime in the future I plan to add a Monarchy DIP or even a Pace Car after the AE. What about kmixer...?!?
This shouldn't matter. I have used both 32 bit & 64 bit Mac operating systems with the ae. I also use the DIP after my ae or apple tv's before the external dac
Good to hear than Mac 64 bit OS doesn't affect AE playback. As soon as my optical cable arrives I will grab an AE and start setting it up. Hopefully 64 bit XP won't give me any problems; I might be back on here putting up an S.O.S. next week. Any 64 bit XP Airport Express users out there with advice on settings? I read a post last night about a test that proved iTunes bypasses kmixer. So maybe that won't be a problem?
Turns out it won't work. The AE setup booklet says service pack 3 is required for XP, which is not available for XP 64 bit. I do have an old Vaio which I use as a holding place for my music library until I get the 64 bit laptop cleaned up, so I tried to install the AE on that, but it's hard drive is filling up and it is 5 years old. I tried to install XP SP3 on it and it locked up, and the AE's Airport utility hammered its wireless settings. I practically had to rebuild the Vaio last night. So the AE is going back. Hello USB audio!