Yellow or white indicators ?

[douglasr]

I'm considering selling my S2000 next year and the Boxster S is on my shorlist. I was looking at the Porsche UK site and I'm confused by the lights. One ad lists litronic lights on a 2000 car and the indicators are white. Another 2000 car has litronic lights, but the indicators are yellow.
I've also seen 2.7's with white indicators.

Can anyone explain..?