Since Emacs version 19 patchlevel 22 or so, there has been both a perl-mode.el and support for the perl debugger built in. These should come with the standard Emacs 19 distribution.
In the perl source directory, you'll find a directory called ``emacs'', which contains several files that should help you.
Note that the perl-mode of emacs will have fits with main'foo (single quote), and mess up the indentation and hilighting. However, note that in perl5, you should be using main::foo. By the way, did we mention that you should upgrade?
Other resources at this site: