You just need to mark it as deleted in the admin web interface. RMS noted it would be good to keep track of person that was removed from the system; by marking it as deleted, we do so.
- As savannah super-user in the web interface, navigate to Site Administration > Main page > Browse users
- You may search for the user using the search box.
- Use the > "[Delete]" action on the appropriate user.
- Do not remove it from the database by hand.