I realize that you were asking someone else, but did you read the link I provided earlier? Maybe it wasn't independent enough for you. Here is the Snopes link debunking this claim.
http://www.snopes.com/politics/obama/security.asp
So, let's recount. Three lawyers, one of them ex-military, all with a background in security checks. A non-partisan site. Covered on another non-partisan site. That articulates one opinion on the issue there.
Or, we could go with three anonymous guys who know some people in the military, used to work at an aviation company, and have a relative who knows something. Yeah, that'll work.
Come on guys, you've got to do better than that. I would love to believe you. I have no personal stake in this matter. Just give me something, anything, to go on here. I am pretty sure that criminal activity will cause you to not pass a security check. So, you could start out with a list of convictions. Failing that, let's hear something equally compelling. If it is so clear-cut an issue, it can't be difficult.
PS: X5Guy: Yes, I believe Obama has faults. We could start with his approach to free trade, his intelligence, etc, and go from there. But the question was why he couldn't get a security clearance. And accusing all Obama supporters out there of being blind fanatical sheep is insulting. Yes, I am sure there are some sheep, on both sides.