Not real. Who would sit there that long and talk into a phone with no one on the line. Naw, not real. Funny as hell though.
Still not sure if it's real or not, but here's an article with more detail about what happened. The guy is from Louisiana, so it wouldn't surprise me if it was indeed real! http://www.mercurynews.com/mld/siliconvalley/business/columnists/gmsv/11059275.htm