Rep. Henry Waxman, considered the meanest dog in town by the GOP, is still sniffing around the White House for proof the president lied when making the case for going to war in Iraq. We hear that he's been quietly summoning former Bush aides, especially speechwriters, to testify behind closed doors about what they knew and how they phrased his words on the issue. Whispers hears that one called in was John Gibson, a former National Security Council speechwriter. He wouldn't spill to us. The committee had no comment either, but an administration official says, "It is yet another item on the ever growing fishing expedition list from Representative Waxman."