If you're not adverse to a little sideways work, run Devel::DProf on your code as the debugger, then use dprofpp -T to print an execution graph.

With a bit of massaging (uniq, or a five line Perl program), you can get a list of all of the unique functions called. They're reported in the form

main::BEGIN
   lib::BEGIN
      vars::import
[download]

Your command line would look be perl -d:DProf forum.cgi.