You should host the files for this modification somewhere, there are probably a lot of people who would donate BTC for it.
I suppose I should try and take the effort to rebase it off a current vanitygen. Was kind of hoping to get more familiar with github at some point and do it as a proper branch/pull request for vanitygen but it never really happened and I guess no one else picked it up and ran with it either.
I think it would be an awesome contribution, I'm surprised samr7 hasn't contacted you to make it a part of the distributed package...