In my case, I think, it's a different issue
The camera is looking for the cleanest edges, while changing the focus. If there is not enough light to produce the picture w/o noise, the eges are drowned out, and the focus cannot be registered. I can actually see it happening on the built-in display
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OK, George W. is deceptive to be sure. Dissembling, too. And let's not forget deceitful. He is lacking veracity and frankness, and void of sooth, though seemingly sincere in his proclivity for pretense. But he did not lie.
[link|http://www.jointhebushwhackers.com/not_a_liar.cfm|Brian Wimer]