I just recieved a phone call along the same line. It was a male caller and did not speak very good english. Claiming to be from the IRS and that a law suit was claimed against me. At the end he stated that if I did not call him back he wished me good luck in handling the problem.
Sure it's a scam. If it's what's being reported on here, you're only going to hear about it by mail, not phone calls. Unless YOU'VE initiated contact with the IRS, you'll hear from them only in the mail. Don't waste your time messing with these fraudsters and ignore their calls and unknown numbers.
I called this number back on another line he asked for my name and I told him if it was the irs he would know who he was calling. Then he threatened me and said if I don't give him my name he would come to my house. And I asked him if it was a threat and he started laughing. Dude is a stupid Indian with phone number 7164063365 comes up as New York number and it's a major scam dude doesn't even give you name in the voice mail it just says this message is for you. Don't call back and just report the number.