A much talked-about Newsweek story offers more details on that strange encounter between Barack Obama and Joe Lieberman on the floor of the Senate last week:

In a brief but animated Senate floor confrontation last week, according to a campaign aide who asked for anonymity when talking about private discussions, Obama told Lieberman he was surprised by Lieberman’s personal attacks and his half-hearted denials of the false rumors that Obama is a Muslim. (The aide says Lieberman was “strangely muted” during the exchange; a Lieberman spokesman says the chat was “private and friendly.”)

The anonymous “campaign aide” is clearly an Obama source, given that this person characterizes Obama’s frustration with Lieberman as being based upon the Connecticut Senator’s “half-hearted denials of the false rumors that Obama is a Muslim.” I did a brief search to find these “half-hearted denials,” and the only story I found was this one, which appeared on the New York Observer website February 1. Here’s Senator Lieberman:

“The one time that I confronted it, I was campaigning in Florida for Senator McCain. I spoke to a large group and a man stood up and asked me about it, or he referenced it. And I said, of course, that I know Senator Obama pretty well. Obviously one’s religion is a matter of choice. Everything I knew said he was Christian. So, I don’t know how widespread it is but that’s the one time I confronted it. And of course the most important thing is that Senator Obama said it’s just not true.”

Never mind that this is the only incident on record (at least the only incident I could find) in which Lieberman was confronted by said rumor. This is “half-hearted?”