I'd forgotten Damien's link above, but you can also get confirmation from this extract copied from the final results published 26.03.02 - easily accessed from the 'news' button in the advfn header
Preliminary results for the year ended 31st December 2001.
Chairman's Statement Oystertec Plc Year Ended 31 December 2001
.....The intangible fixed asset is the cost to the Company of intellectual property purchased at the time of the Flotation. Creditors due after more than one year includes £2.87m consideration relating to this purchase being payable in accordance with profits earned under a tranche payment structure, which takes effect from 31 December 2004 "
(I suppose the £13K went on clearing up Pedro D's alleged golf club corporate hospitality bar bill (bite my toungue, in this season of goodwill to all men!)