You didn't hear about it? Glenn Reynolds did --
SARKOZY MOCKS OBAMA at U.N. Security Council
Here's the full transcript (see p12) of the meeting along with Sarko's remarks as prepared in French. It's hard to see the mockery. Sarko is of course blunt and both he and Obama by then knew of the Iranian bombshell that would be coming the next day. And French foreign policy is fairly hawkish on Iran; remember it was the Socialist candidate in the last election who thought that Iran shouldn't be allowed even a civilian nuclear program.
Maybe some read it as mockery because the remarks were delivered in French but read in translation by Anglophone newspapers. Not everything said in French is going to be flattery. Sometimes they will be saying actual tough stuff.