And I guess if the Coldsync client program is written in Perl, there is
a good chance it could get ported to other platforms without having a
major re-write of the server based code, which means Windows and MacOSX
become natural extensions of the system.
I'm not sure how much you'd gain by writing this stuff in Perl.
For one thing, the existing C code already contains an implementation of a
bunch of stuff, including the various protocols involved in syncing. IMHO
it's good thing to continue using this. If the core code changes, you only
have to fix it in one place, rather than two.