This is great. Thanks for your efforts!
I have added a page to the wiki:
http://www.firephp.org/Wiki/Libraries/PerlFeel free to blog about it to get more feedback than what you will get from this forum.
I am working on a language-neutral version of FirePHP which will be released later this year. It will implement the same Wildfire protocol as the FirePHPCore class so your code will work with the new extension as well with only minor modifications.