Pete Doherty's jail sentence has pal Amy Winehouse laughing hard.

The "Rehab" singer, 24, reportedly displayed an unusual reaction after hearing that the Babyshambles rocker had been sentenced to 14 weeks in jail.

A friend of Winehouse says, "Amy's first reaction when she heard was to laugh. Pete had told everyone he was just going to court for a quick appearance and had no idea he was going to jail."

"She just laughed and kept saying, 'I can't believe it.' Pete's just a comedy character to Amy. She thinks he's a bit of a clown."

Doherty, 29, was given the sentence at West London Magistrates Court earlier this week for drug use and failing to attend probation hearings on time.