can anyone identify this rocket?

Hi,
can anyone identify this suborbital rocket used for Sandia's "Red Crow"
experiment in 1998. I guess it is a Castor with some kind of upper stage.

http://www.sandia.gov/locations/ktf/redcrow.jpg

" On April 17, 1998, Red Crow was launched from the Kauai Test Facility for
the Ballistic Missile Defense Organization to assess the effectiveness of
electronic countermeasures against US Theater Missile Defense systems.
Information gathered from this experiment will be instrumental in enhancing
US defenses against possible countermeasures employed by adversaries. The
Sandia Red Crow team developed the booster system, integrated a payload
suite within the launch vehicle, and conducted the launch operation at KTF.
"

Gunter Krebs
http://space.skyrocket.de