Statute of Limitations?

I am being pursued for a small credit card debt from 1998. I heard nothing from the company and have made them no payment since then. I understand that this is covered by the Statute of Limitations as it is over 6 years old. However, the collections agency told me that as I had not informed my creditor that I had moved house, the Statute does not apply. Is this correct or are they trying it on with me? Thanks for your help