git merge with tkdiff fails (extra operand)

Hi,

I'm running Git 1.5.3.7 under SuSE 10.0. After pulling and getting a 
merge conflict, "git mergetool" by default is configured to run tkdiff. 
Unfortunately, tkdiff starts with an error:

diff failed:
diff: extra operand
`Amira/QxViewer.cpp.REMOTE.28414`
diff: Try diff --help for more information.

I'm not sure whether the error is with the tkdiff integration into Git, 
or with tkdiff itself (as it refers to the help for "diff").

Any insights?

-- 
Sebastian Schuberth