The singer, who was jailed in September after he crashed his Range Rover into a photography shop, was apparently 'relaxed and composed' while he served his four-week sentence.
According to The Sun, Wandsworth prison convict Sahodree wrote to jail newspaper Inside Time to say he had come face to face with the former Wham! star.
'When George [first] came by the food server he looked anxious,' Sahodree said. 'My colleagues were in awe of him and speechless, but I approached George and to reassure him I said 'George, my wife is your biggest fan'. He told me to say 'Hi' to her. The next day when George came to the server he looked more relaxed and composed. He was very polite and pleasant.'