This script tdcopy.cmd assumes that the source trees for exchange are available on
\\tdsrc. The syntax is easy:
tdcopy -build build-number [-doit]
the build number is the number of the build that you want to sync to. -doit means
do the copy.
each file is diffed, and files that have changes are checked out, copied to *.prev,
and the current file copied down. You must then go through and confirm the changes
and use sd submit to check them all in.