Kiefer Sutherland started his 48-day prison sentence yesterday.The '24' actor - who was arrested for driving under the influence (DUI) in September while on probation for another drink-driving offence in 2004 - was sent to Glendale City Jail, California. Jail spokesman officer John Balian said: "Mr. Sutherland is very polite and humble. He was very cooperative during the booking process."He will be issued an orange jumpsuit, and will be housed alone in a cell, since he'll be a long-term inmate." Sutherland has been given the job of 'inmate worker' - serving breakfast, lunch and dinner to his fellow prisoners - and consequently will be allowed to walk around the jail "around 75 per cent of the time". The rest of the time, the 40-year-old actor will be locked in his eight by ten foot cell, which only contains a toilet, washbasin and water fountain.Sutherland - who has three stepchildren and one biological daughter from his two failed marriages - will receive two hot meals and one cold meal each day, taken from a menu of corn flakes, turkey sandwiches, meatloaf, macaroni and cheese and chicken 'a la king'.The actor - who plays counter terrorist agent Jack Bauer in the hit US TV show - reportedly looked "contrite" as Judge Stuart M. Rice ruled he would spend his sentence at the Glendale jail when he reported to Los Angeles' Metropolitan Branch Courthouse.Rice ordered Sutherland to complete an 18-month alcohol education program and attend weekly therapy sessions for six months.A statement from the Los Angeles City Attorney's Office read: "Sutherland will be serving the 48 days in the Glendale City Jail, with no early release and no good time or work time credit, so we expect that he will serve the entire 48 days in jail."At the time of his arrest, Sutherland released a statement saying: "I'm very disappointed in myself for the poor judgment I exhibited recently, and I'm deeply sorry for the disappointment and distress this has caused my family, friends and co-workers on '24' and at 20th Century Fox."I appreciate the support and concern that has been extended to me these last weeks both personally and professionally."Kiefer's arrest in September was his fourth arrest for DUI. In 1989, he was arrested for DUI and carrying a concealed and loaded weapon, but was only charged with DUI.In 1993, he was arrested again for DUI, and performed 211 hours of community service, after being given the option of the community service or 12 days in jail.In 2004, he pleaded guilty to one charge of DUI, completed 50 hours of community service, and attended an alcohol treatment program.He was also sentenced to 60 months of probation, which he violated.