If the modules are pure Perl, and if the Perl versions don't differ very much, then you might be able to get away with that. (It doesn't strike me as a great idea, regardless.) But Perl-GTK2 is not
pure Perl. In that case you are very likely to run into native code library mismatches. I'd say "certain" instead of "very likely" in this case because you have both a Linux platform issue (what glibc did AS use to build their stuff? It's likely statically linked into their Perl, but their modules will expect it and other libraries to be just so.) and a Perl minor rev issue.
"Even if you are on the right track, you'll get run over if you just sit there." - Will Rogers