Despite bad science, French lab tech incompetence, and conspiracies against foreign riders, Patrick Sinkewitz has apparently said "ya got me":

Former T-Mobile rider Patrik Sinkewitz, who was among riders in this year's Tour de France to test positive for drugs, has decided not to have a second urine sample analyzed, the German Cycling Federation said on Tuesday.

"Patrik Sinkewitz's lawyer, Michael Lehner, has informed us by fax that his client is foregoing the opening of the B sample," the Federation (BDR) said. "Mr Lehner said that a public announcement would be made today."

source: VN

The German rider will now likely be suspended for two years, although there is some speculation that he will become a key witness, like Jörg Jaksche. Depending on how much he tells this could mean a reduced sentence under UCI rules.