Since it works on other hardware, I guess we have to point the finger at Lenovo here. Unfortunately you're using a product released over 10 years ago now - it was never designed with current hardware platforms in mind - At the time it was made, everyone was religious about sticking to the agreed specifications, now things are a bit more complex since the introduction of USB, SATA etc...
I was afraid that would be the answer. Well I suppose if there's nothing we can do, there's nothing we can do. I can't see Lenovo wanting to do anything to help us out, I'll see if there's a bios update or something anyway. Might be a good reason to expedite the upgrade to EEM.