I did the transition aswell from PHP to Perl quite some time ago. I wasn't really eager to learn perl either, but it was a necessisty at the palce I worked back then.

My main problem at first was, that I didn't find the info i wanted (talk about wrong researching, or just trying to avoid to learn perl). What I missed the most was the documentation www.php.net offers.
Since I had to do all the stuff at work in perl, I got myself a copy of the camel book from o'reilly, and started from there. Plus I got some source code of internal made perl scripts, so that was helping me getting started aswell. Sooner or later I found out about www.perl.com, perlmonks, and some other sites I forgot about meanwhile and since then i'm hooked to perl and don't want to miss it.
here's a nice comparison of perl vs. php: Web Automation: PHP vs. Perl vs. PHP

Starting with perl can be very hard, specially if you aren't eager to learn it and would rather stick with PHP. But once you've gotten into perl, you don't want to miss it anymore.

.emanuel