Memory diff't sizes/speeds - still dual channel?

In putting together this computer: ASUS m3A78-T with AMD Phenom x4 9850, I ordered 2x 1GB 1066 OCZ memory. Then I got some 2x 2GB 800 OCZ memory. Both sets have CAS 5 but are different speeds and sizes. I've done exhaustive research on this and can only find bits of answers but nothing to my specific situation. Is this ok? What are people's opinions? Will dual channel still work? Should I just get 2 mor 2 GB 800 from OCZ. I won't mind if I need to scrub the 1066 2x 2GB it was quite cheap after rebate. The motherboard has 2 channels, 4 slots, and can take a max of 2GB in each slot, for total max of 8GB. It will do 1066 but only on one channel.