issue importer does not transfer watchers on homegrown-zips

I've migrated my project "alembic" to git, and in so doing I renamed the old project to "alembic_moved_from_hg_to_git", created a new project "alembic", and added the code, as well as the full issue database from the old project using the importer tool.

But all the "watchers" were lost, even though the watchers are in the db-1.0.json file. I had to personally click the "watch" link for all the issues myself, and there is not even an easy way I can send a message to all the previous "watchers" that the issues have all been moved, except for sending a message to all 64 of them individually (a prospect I'm not excited about).

There needs to be some way to get the watchers onto a new tracker once an issue import is performed, either allowing them to go in directly or at least some system of notifying them.