Comment 3 for bug 530793

One possible solution might be to use a different interpreter for the application itself and the command execution.

If you're using virtualenvs that don't fall through to the system site-packages, then you have to install dreampie and pygtk into your virtualenv to make Noam's solution work. And pygtk isn't installable via pip on Linux, so even this (rather ugly) solution isn't workable.

This is a dealbreaker for me, although DreamPie looks very nice otherwise.