The Tk module isn't written using pure perl, it uses some XS code, which is converted into C and compiled as a shared object (shared library). Perl then tries to load it when you request the Tk module, and that's where its failing.

My best guess at why its having problems finding the symbol is that there is a mismatch between the perl executable and the version that the library was compiled against.

You probably want to start investigating by recompiling and reinstalling the Tk module and make sure all the tests included with it run ok.

--
integral, resident of freenode's #perl