It appears that the only XS component that has Zlib statically linked (That I could find anyway) is /usr/lib/perl5/site_perl/5.6.1/i686-linux/pdflib_pl.so (on my machine YMMV) which is used by 'pdflib_pl.pm' (there are also Python and Tcl versions on my machine) - so apart from this module simply rebuilding the Zlib shared library should fix the problem.

/J\