Perl Cookbook has excellent coverage of sockets and client/server programming (Chapter 17.)

I'm in the midst of porting some Java based c/s applications to Perl. Our stuff is very much cross-platform; the Java code had to run on Windows, Linux, and (*gasp*) even OS/2. I can attest that Perl is just as robust as Java in its socket/networking support. And I haven't had to worry about the particular platform so far.