Florent, why Zope Product would require Localizer to be installed to function correctly? We've just removed all gettext form .dtml files to make it work. ZMI is mainly in English and that is pretty good solution until Zope provide Basement for Product l10n. Until that time I see no reason to force users to install Localizer just to see ZMI of that one product (NuxDocument in our case) in other language. Note, there is no fallback mechanism to make it work without Localizer installed.
Feel free to write one, it will be included in the next release. If you don't, it's in my TODO list for the project.
It already exists, see the module LocalizerSupport.py in the Localizer product. ZWiki uses it. -- J. David Ibáñez, http://www.j-david.net Software Engineer / Ingénieur Logiciel / Ingeniero de Software