I'm guessing Jennings' birth name is the main name on her profile, and the birth mother just searched for that. She was apparently adopted at at least age two, so she certainly retained at least her first name.

This has happened more than once on MySpace. There was a recent news report about a guy who found his daughter this way.

Time to cue the blooper video!

http://uselessjunk.com/article_full.php?id=19098