Maybe I missed something Kholi, but if I put my D90 in manual mode, and then turn the aperture ring of my 50mm 1.8 lens (and get the EE error), it won't let me engage live view mode.
Do I need a non-cpu lens? Your write-up made it sound like this lens would work:
http://www.nikonusa.com/Find-Your-Nikon/ProductDetail.page?pid=2137
Right You need a Non-Cpu lens. For one with a CPU you have to do this:
1. Aperture Priorit mode
2. Put the Lens @ F22 or Auto Mode
3. Set the Aperture with the Aperture Wheel on the front of the camera to f5.6 or 8 (electronic aperture)
4. Activate LV mode while pointing at the source
5. THEN unlock the wheel to engage the manual Iris. It'll throw an error but it's fine for recording.
That should do it.