At least that's what Birnbaum said when sending this piece:
Did He Kiss Joe? By William F. Buckley Jr.
...the narrative returns to the 50th anniversary dinner, at which Lieberman and I were seated at the same table. In the days that followed, the Democratic blogosphere gave Lieberman hell for showing up at my party, reading into his presence there ideological courtship, never mind that Lieberman has been a stalwart Democratic 95 percent of his times at bat.
But in looking into Lieberman's vulnerabilities I discovered in Wikipedia this item: "Following his 2005 State of the Union address, President Bush, after shaking lawmakers' hands, abruptly grasped Lieberman's head in both hands and kissed him on the cheek. At first, Lieberman's staff humorously referred to the embrace as 'some kind of Yale thing.'