Update in my case.
My one was refused to repair by Japanese "Apple authorised" repairer based on its serial number.
According to them, there are several types of parts combination and mine is recorded as one which is not supported on this islands. I am suspecting rather than being such an electronics concern but being commercial issue, anyway mine is not supported.
Recently, mine shows inside camera normally without problem. Right after restarting the camera application last time by whether means of restarting entire machine or double clicking the home button, it was showing shutter (or perfectly closed iris) and flicker with blue band repeatedly. But after some days, it start working normally.
My suspect of potential issue is as follows.
1) Calibration logic is too strict against something on the camera module.
This incures a software counter measure to ease the boundary number.
2) DMA hardware issue on the particular A5 chip instance (production torrelance).
This incures necessity of issue of an errata by the semi-con manufacturer and software counter measure.
My one's awdd_$date... is always being sent to Apple and they can see it. Expecting earlier release of iOS 5.1.