After an eight month search, President George W. Bush has appointed Sada Cumber, a Karachi-born Pakistani American, as special envoy to the Organization of the Islamic Conference.  Cumber, who received his BA and MA from Karachi University, was chairman of an Austin, Texas-based technology firm till his appointment.  He has received a number of government appointments from Texas Governor Rick Perry, a Republican, and is active in Ismaili Muslim and interfaith activities.