From Juan Cole again:
Blitzer then revealed that he had discussed the Khan case with US National Security Adviser Condaleeza Rice on background. He reported that she had admitted that the Bush administration had in fact revealed Khan's name to the press. She said she did not know if Khan was a double agent working for the Pakistani government. (!!!)
So the National Security Director has confirmed that the Bush administration leaked the name of the agent responsible for proiding essential intelligence, thus comprimisting any future usefullness he may have provided. It could be speculated that the agent's cover was already blown, but Rice's comment that she did not know he was a double agent either illustrates an unbelievable failure of intelligence, or they are just covering. The Pakistani reaction certainly would suggest he still had some further use before this incident.