Her name was Mary. Initially, the rumor identified the intern only by her initials (Bubba must have gone through the alphabet twice). She was killed in a strange Starbucks robbery where nothing was stolen.
I love FR research. I just remembered that alamo-girl wrote extensively about this.
http://alamo-girl.com/03159.htm
The full list of people attributed to the Clintons is at:
http://alamo-girl.com/0463.htm