Question : Can the same Pagefile.sys be used on a dual-boot WinXP-32bit/WinXP-64bit?

My work laptop is set up with Windows XP - 64bit version. Since the Cisco VPN client (et. al.) won't work in 64bit Windows I also have Windows XP - 32bit version on a separate partition. My primary OS is on drive C:\

Both partitions (C: and D: drive) have a 2GB pagefile.sys in their root directory, but each OS only uses one of them while the other just takes up space.

(I think) I have made Debian and Gentoo use the same swap partition without problems.
Is it safe to point both OS-es to use the same Pagefile.sys, removing the other (or just use both of them as a 4GB pagefile)? Only one of them is running at a time.
Any formatting/byte-alignment issues? - It's just used as memory so I would think it's not a problem...
What could go wrong?
How would I set it up?

Answer : Can the same Pagefile.sys be used on a dual-boot WinXP-32bit/WinXP-64bit?

Absolutely no problems, unless you intend to run both OSs at the same time through VMWare or something.

Windows does not use the old page file data for anything, so on each boot it will just ignore any "incompatibilities".
What you would to to set it up is to set a page file on a common drive, and reboot into the other system.
On the second system delete the pagefile.sys you just created earlier, then set the second system's page file to the common partition.

This will ensure that exactly one pagefile.sys exists on the common partition, and both OSs are pointed at it.
You should also set both systems to use a fixed page file (equal top and lower bounds) and defrag it once using pagedefrag from sysinternals.
http://technet.microsoft.com/en-us/sysinternals/bb897426.aspx