dont acknowlege the debt, there is a lot on this forum about debts over 6 years called statute barred. I searched for it and found a standard letter to send from a guy called connmankiller who seems to know a lot and is very helpfull.

This is just one thread to llo at and see the letter template but dont call them and dont admit the debt ever just send the letter and postal order and see what happens - they probalbly bought the debt from the bank and are just chasing to see if they can get anything.

http://www.moneysupermarket.com/community/forums/t/statute-barred-mess-up-34135.aspx