Or the delivered library files? I would recommend the Core library since whatever I uploaded is pretty old now. If you are using the Zend stuff, I don't know if it works or not and didn't test it.
Have you been able to get any output to the console from firephp in any other way?
I'm working on an updated version which will fix some issues and have a test page but I haven't had time to finish it.
Above all I try FirePHP
I followed the steps of http://prendreuncafe.com/blog/post/2008/07/20/Debug-PHP-facile-avec-Firefox-Firebug-et-FirePHP
I got the same result so I'm sure that works FirePHP for ezpublish I use version 4
in template I wrote the following line: {"eztest"|ezfire("THIS IS THE LABEL")}
The "Fatal error: eZ Publish did not finish its request. The execution of eZ Publish was abruptly ended, the debug output is present below." error occurs ONLY if the ezfire line is in the template?