How are you trying install it? From the module on CPAN, the downloadable tarball from TkZinc.org, or an RPM for some specific distribution? Zinc was originally made for TCL, but has been ported to Perl. If you use the module from CPAN, it should work. The tarball from TkZinc.org is designed for TCL and has a special subdir for building the Perl/Tk version.... read the README that is in the Perl subdir, run export2cpan, then build according to instructions.