Vista - Minor Remote Desktop Issue (Vista to XP)

I have three computers at the moment: two with Vista Business, one with XP
Media Center Edition. Remote desktop connection functions perfectly between
the two Vista Business machines, and it functions almost perfectly between a
Vista and the XP. There are just minor issues.

When connecting from Vista to XP I am unable to copy files from one computer
to the other (copy & pasting files from one machine to the other does not
work and when going to My Computer on the remote machine the local drives
are not visible). Also, less of a concern but still an issue, is that
connecting from the Vista to XP I am unable to wake up the XP if it is
asleep/standby whether using remote desktop or freeware like WOL.

So copying files and remote wakeup both work for me between my two Vistas,
but not between Vista and XP. If anyone knows of a fix for these issues, it
would be a big help. I have a feeling this is just how it is though and
I'll need to resort to something besides remote desktop for these other
tasks.