VAT on unpaid invoices

I'm just doing my year end, and my accounts software says I have some
VAT on unpaid invoices as a liability on my balance ***.

At year end I didn't happen to have any unpaid invoices, ie all the
invoices raised before the end of March 2006 were paid before the end
of March 2006.

Given this, how is it possible that I have VAT on unpaid invoices? I'm
clearly missing something somewhere...

--
Simon Elliott http://www.ctsn.co.uk
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