VN has the story. Here's your money quote:
“The pressure was overwhelming,” he said. “I was looking ahead to the Tour and realized I was not in the kind of condition I had hoped to be. I am just a man and a man who made a decision at a moment of weakness. I made a bad decision and I have to pay for that.
And that is pretty much the doping problem in a nutshell. He says Holczer knew nothing. Sounds right; Holczer is about the last person to whom you want to reveal your dark secrets. Anyway, boo on you Kohl for cheating. Yay for confessing. But... boo for cheating.