A strange bug

I'm having the strangest bug.
When starting lispworks (lw professional 5.1.1, windows xp sp2, french 
keyboard), It somehow press the backquote key on the keyboard.

The result is that the first thing I type in any window (lispworks 
windows or any other window) will be prefixed by a backquote.
On french and belgian keyboards the backquote is used with some voyels 
to make accented characters (it doesn't show until you press another key).

Now that wouldn't be a problem but It does it with delivered 
applications as well, and that can be pretty annoying.

I tried disabling everything in my .lispworks file and still the same 
problem.

Did anyone have such problem ? I have no clue as to what I could do to 
fix this ...

Thanks in advance,
Sacha