We had the same problem with our GTi, upon further investigation we could see the matrix had been leaking within the enclosure it sits in, the matrix has been replaced with a new item and the safety valve has been removed altogether running the hoses direct for return and feed etc.
Problem no longer persists, the vw part quote is of the same part number for the MK2 & MK3 now as a revision, bascially it's a MK3 item all round now, better core, valve no longer in use.
We also have a 1.8 Driver which has never been recalled, we checked with VW UK to see if there was an issue or was is just an over sight, answer being not all the MK2's had a recall, the last/later models did nor require it due to matrix specification changes.