Instansiating a specific PLL

Hi,

I am using the PLL embedded in an ALTMEMDDR2 controller to derrive system clocks as well as DDR2 timing & clocks (SOPC system). Is there any way I can define the specific PLL to be instansiated by Quartus? There are 4 PLLs with the Cyclone III device I'm using. I would like to instansiate PLL3, how do I do this? Quartus alway opts for PLL1.

Thanks

kohagan