We got the call on Saturday in US; and the first call just hung up.
Calling back just says "Thank you for calling IRS" and then just beep.. of course I did not elave any details, as there was nothing to respond to.
Jan 13th, 2014
The voice mail said he is calling from Internal Revenue Service and there is a problem, I should call him back. The call came in at 7.34am on 12/18/2013. I know IRS office is not open at 7.34 am and they never call on the phone.