clken for FIFO mode of TriMatrix Embedded Memory?

Dear all

I'm currently optimizing my Stratix III design towards lower power consumption and implementing the "Reducing Memory Power Consumption" as suggested by chapter 14 of QII handbock. Introducing clken works very well for ROM, single port and dual port RAM use of the memory blocks. However, as it comes to FIFO mode, I wasn't able to make out the MegaWizard button that builds in the clken.

Does that feature not exist for FIFO mode, is it built-in per default or do I have to build my own FIFO based on an orinary RAM to be able to use that feature?

Regards,

Peter