The Central Intelligence Agency paid tribute yesterday to a case officer who was killed in the line of duty in 2003. The agency formally acknowledged the death of Gregg Wenzel, who was on assignment in Ethiopia when he was hit by a drunk driver. Wenzel, a lawyer from Sarasota Florida, was posing as a foreign service officer. He was a member of the first case officer training class to graduate after September 11. Also: the CIA disclosed that another member of the National Clandestine Service was killed in 2008, though the agency would not provide details.