New firmware released for 645D and 645Z. Seems to be about adding compatibility for the new HD PENTAX-D FA645 35mmF3.5AL[IF] lens and general stability stuff.
Version 1.22 for the 645Z is here:
Latest PENTAX 645Z Firmware Update : Software Downloads | RICOH IMAGING
Version 1.32 for the 645D is here:
Latest 645D Firmware Update : Software Downloads | RICOH IMAGING
I take no responsibility for these by the way - just passing info. on :-)