On the given url is an enhancement for VIM delivering a vim as a bonobo component. Also there is a patch available that evolution uses this component as editor component. I would be very happy when i can emerge it easily via portage.
I would love it too. Unfortunately, none of those patches have been updated in 2 years, and they don't apply to even remotely recent versions of vim or evolution. So, it can't be done, unless someone wants to take over the development project.
