Unknown NT workgroup appears in NetNeigh

We just noticed this morining a new workgroup in Network Neighborhood, one we’ve never seen before and know nothing about. It is called Autor_trh and in it is one computer named Mok-It. When I try to access Mok-It it asks for a logon name/password, which of course we don’t know.

I checked user mgr for unknown users, there are none, and server mgr for any new entries, again there are none. There also are no new trust relationships set up.

Has anyone seen something like this before? We arevery concerned about where this came from, who put it there, etc.