Being request for a tax that I don't even know

I lived in Rhode Island during 1993 and 1995. At that time, I owned a 89 Honda Civic which was of value $4400. They started a property tax for owned cars in 1995 right before I left RI. I was not aware of the tax at that time because the first filing for that tax was after I left. Just now, after almost six years, I received a letter from a debt collector, saying that I owe about $550.00 for the motor vehicle tax for registering the car for 226 days in 1995. Although unpleasant, I am willing to pay the tax, but my question is that the amount I owe now includes the interests accumulated for the past six years, during which period I did not even know I owe this money. I am really upset about this fact. Is there a way I can just pay the original amount?

Thanks,
A frustrated graduate student

I am not an attorney and not a CPA. . .

I don't know specifics about your situation, but MOST debts are not valid after 6 years. Usually that is the length of time that is considered long enough for your creditor to locate you and file a motion. I would investigate your options before paying the cash.