When you recompiled Perl, you probably changed the default module search path. Although HTML::Parser is on the box, it's probably not in the search path. (perl -V will tell you what's in @INC).

You might just have to change your @INC locally (PERL5LIB, use lib, etc) to help Perl find the module.

Additionally, you might have to recompile some modules. I suggest a case of beer and a trip to your sysadmin's office. If he's in a different location, you can use one of those services that send beer baskets :)

Good luck :)