I just received the same messages on my answering machine saying "The IRS is suing you. please call 209-542-2249." This is a SCAM, because the IRS will send you a letter in the mail.
Just got same call from this number about IRS suing me. I hope no fools get taken by this scam. I also hope whoever is behind it falls into a deep dark hole where they are slowly eaten by whatever feeds on dung.
Received the same call from IRS and they are suing me. I WILL NOT call back. Never know what info they get just from the return call---first they have a live person if randomly calling numbers.