Allowing Users to add other users from Self Service

Hi all:

I have an RT installation that we are expanding to encompass some 

“hosted” ticketing as part of a larger project. In effect, we have a
dozen groups with RT that are part of one company. They have requested
that we allow them to add other people within their groups to a ticket.

I see the watchAsAdminCC there, but I don't see any way for them to add 

others. I was wondering if anyone had any suggestions.

The groups are set up in a hierarchy where there are a few "core" 

members that belong to the core group, then a dozen other “team” groups
that report to the core group. The core group members are also members
of every team group so they get added to every ticket.

The only thing I could think of without getting too fancy was to add 

a customfield to the ticket that only members of these two groups had
rights to, and allow the core team the ability to choose one of the
other teams from a drop down, then add a scrip to recognize changes to
this field and add groups. That seems very cumbersome.

Thanks in advance!