This jet is the Williams V-Jet II.  Here is a link to more info, http://www.lerc.nasa.gov/WWW/AST/GAP/wi0697.htm

and here is some inside poop -- Rutan didn't like the V tail and thought a single vertical stab would be better but the plane was a marketing tool for Williams engines and had to look snazzy so Williams insisted on a V tail.  Thank you to Don Odum who's format I am shamelessly copying for this presentation and who contributed this information.  I REALLY have to start doing a better job of documenting the photos I take.