Hello If you would like to debug a mod_perl application this links may be usefull for you:
general concepts:
http://perl.apache.org/docs/1.0/guide/debug.html#ptkdb_and_Interactive_mod_perl_Debugging
some patch for working with ptkdb:
http://article.gmane.org/gmane.comp.apache.mod-perl/7562/match=ptkdb
You sould remove spamprotection, and maybe remove the next line:
$ENV{DISPLAY} = $r->get_remote_host.':0.0';