Max Cleland, a former senator from Georgia and one of five Democrats on the federal commission investigating the Sept. 11 terrorist attacks, is expected to resign within weeks, creating a vacancy with only six months left in the inquiry, commission officials said today. Mr. Cleland’s intention to resign from the 10-member commission has been known since last summer, when Senate Democrats announced that they had recommended him for a Democratic slot on the board of the Export-Import Bank. But the timing of his departure became clear only last week, when the White House formally sent the nomination to the Senate. Full Story