It would appear that it requries the nspluginwrapper to work. This is new ground for me. I don't suppose that I could pull the deb and install it with dpkg, have it appear in aptitude as locally installed/obsolete and have it work? Or does it rely on newer versions of libs than are in Etch?
When I am in a situation like that I create (if it doesn't already exist) /etc/apt/apt.conf with this in it.. APT::Default-Release "stable"; Then and lenny/testing lines to /etc/apt/sources.list. As long as you have that in your apt.conf apt and aptitude will always keep your system at stable, but you still have testing packages available when needed.