Irs scam. I've called them back 475 times and tied up their phone line all day. I've also put this number out to my fellow scambuster vigilantes! The number is a VOI Magic Jack out of India!
I knew this was an IRS Scam so I offered to give him a Social Security number (which I would have made up). He told me that he didn't need that information because it was confidential. I then offered to send him money via Western Union and he told me to go f*ck myself.