Need help with plugin localization (Segmentation fault error)

I’m porting TinyMCE editor into a worpress plugin which will be hopefully released in a few days.
I’m having a strange problem which is driving me crazy.
It is related to the plugin localization and everything works fine but the image manager popup (which is launched by a toolbar button).
In a few words:Firefox crashes when i try to open that popup outputting “Segmentation fault” error.
I’ve spent all the afternoon trying to find the fix but had no luck at all.
My test environement: apache 2.0/php 4.3.8/firefox 1.0.4
I’ve added
load_plugin_textdomain(‘tinyeditor’);
in top of the plugin file (tinyeditor.php)
and placed the italian .mo file :
tinyeditor-it_IT.mo
into /wp-content/plugins/ directory.
Another note: firefox doesn’t crash if i access the image manager pages directly ex:
wp-content/plugins/tinyeditor/plugins/imgmanager/ImageManager/maanger.php
works fine and strings are correctly translated.
If the same page is accessed from within the editor (via the toolbar button) Firefox crashes.
Sorry for being long,but the problems seems too complicated.
Thanks in advance,ralf.