seeing diffs in Mercurial with a difftool not able to diff directories

On a Solaris 10 Box I have installed tkdiff and configured for usage in mercurial.

Tkdiff can not diff directories, so a
hg diff
in the root directory fails.

But I have no a solution
bash-3.2$for d in `hg status -q | cut -f 2 -d " "`; do
hg diff $d
This takes the status output drops the state column and just uses the file names to
iterate over for using with hg diff.