KW-rscos

As above, have an intermittent start problem on my 98 GTi, Seems to happen more often when its warm, but has happened after it has sat for a couple of hours, basically, when I go to start it, the fuel pump primes, but then nothing?! if i turn the key back and go again, it will then start, but it also starts if I hold the key in the last position IF i hold it there for around 10 seconds?!

The starter is a bosch item about 6months old, and the wiring seems to be ok, certainly nothing obvious. What else could it be?

Regards, Kieren.