Please pardon a bit of a rant:
"I can't get - to work" is almost entirely useless as a problem report. All it says is that something about
- doesn't work the way you think it should. It gives no information about how you think it should work, or how it is working.
Since you don't give any indication of what is happening, it's pretty tough to say what could be wrong. However, I can think of one possibility. IMP has two places to set the language. The first is at the logon screen, and it affects (IIRC) only the logon screen. The second is in the user preferences, and it affects everything else. If you've only been setting one of these, it won't affect the other AFAIK.