What is Porsche using as the factory fill for the manual transmission on the 996 Turbo?

Is it Mobil One synthetic 75W-90 gear oil? (Not even sure if this product is sold in Europe.)

Mobil One is a GL-5. I'm wondering if the Turbo requires GL-4 or GL-5? A lot of people seem to be using the Mobil oil but in the past Porsche transmissions have required GL-4 and not GL-5.

Haven't seen any discussion on this anywhere yet.