very odd asus problem

I have an asus p5ql-se here. It has 6 sata ports, however... if I try and use all six, the bios won't detect any drives plugged into the two next to the 5th and 6th ports. I have to clone a couple of hard drives, and ripping them out and into another case just to be cloned will be a real pain. Is there any logic to this problem?

I thought the P5QL-SE only had 4 SATA ports, including a JMB PATA controller supporting two additional devices.