Hello,
I think the French language pack for Alfresco is only current for version PR6. Between PR6 and version 1.0 we renamed one of the key property files! This means you will need to rename it for it to work:
messages_fr_FR.properties
has changed to:
webclient_fr_FR.properties
and has moved into the "messages" folder with the other files.
Note that since PR6 several new properties files have also been added - this mean the French language pack is out-of-date at present and will be missing many strings.
Thanks,
Kevin