white screen on menu item changes

Hi,

- Since I installed localizer.module, I get a white screen when updating/ saving a custom menu item...
- The db table localizertranslation stays empty after saving/ updating a menu item through the menu administration.
- On the other hand, the menu item DOES get inserted into this table, when I change the menu settings of the related node content page. BUT: Afterwards the menu item won't show up anymore in the menu administration...

thanks