I got a call from this number, too. I called back and a "gentleman" answered the phone. Thick foreign accent. Said he worked for the Internal Revenue Department (I don't believe the IRS has changed its name). Said his supervisor was John Stevens. I tried asking more questions and he hung up on me. Guess the IRS doesn't want my money that badly!
I received a recorded message from this number saying it was the IRS and that there was a lawsuit against me. When I called the number back it rang at least 15 times before someone with a very strong accent answered. When I asked how I knew that this was REALLY the IRS he said why would you call if you didn't think that we were the IRS. AND then he hung up!