Parliamentary "hold"?

A Lone G.O.P. Senator, Unknown, Holds Up an Intelligence Bill

"WASHINGTON, Dec. 23 - An unidentified Republican senator has blocked the authorization bill that sets guidance for all intelligence spending, and the measure must now wait for Congress to return next month from recess, Congressional officials said Friday. The bill, setting broad policies on intelligence matters, is one of the last items of significant business that was left hanging as lawmakers went home for the holiday recess. The parliamentary "hold" was put on the intelligence authorization bill under Senate rules that allow a single senator acting anonymously to delay action on legislation. It appeared to be intended to block amendments dealing with the detention and treatment of captured terror suspects and with intelligence on Iraq".

What an idiot. One of the recorded votes on those amendments was 90-9, and a 'single senator acting anonymously' can put a 'hold' on that?