The weekly seminars on American history at the Coleman Federal Correctional Complex have become so popular, the penitentiary has moved the classes to a larger venue.

It might have something to do with the teacher: Conrad Black.

Sources said the former press baron, who began serving a 6 and a half year prison sentence on March 3 at the prison located 85 Kilometres northwest of Orlando, Fla., is said to be teaching to a "full house," which includes prison staff and custodians.

Lord Black, who once presided over the world's third-largest newspaper empire, has been tasked to conduct the seminars as part of his job in the library at the low-security federal penitentiary.

"He is to be kept busy as a prisoner and the prison is making use of his talents," said a source who asked not to be identified.

In fact, Lord Black is one of a number of inmates conducting seminars or teaching courses at Coleman.

Known among some of the other 2,000 inmates in Coleman's low-security facility as the "billionaire lord," the Montreal-born businessman has made acquaintances and is said to be adjusting to prison life.