[masraum]

I haven't had it happen, but I've heard of similar stuff. The IRS wouldn't proceed like that, and if they left a message to call, they would make damn sure the mailbox wasn't full. I also don't think there's anyway in hell that they would threaten cops coming to get you. If the IRS wanted cops to come get you, I don't think they'd warn you.

It's clearly a scam. It's very, very easy to make your caller ID say anything you want it to say assuming your telco will let you.