Now, more than 70 years later, the tender love song that the ruthless crime boss penned while sitting in the now-defunct California prison is being recorded and released on CD. And an inscribed copy of the music and lyrics to 'Madonna Mia' is up for sale at US$65,000(S$97,000).

'It's a beautiful song, a tearjerker,' said Rich Larsen of Caponefanclub.com, who helped line up musicians and singers to record it.

The story of 'Madonna Mia' begins in a cell in Alcatraz, where Scarface was sent for tax evasion. Capone, who loved opera and jazz and whose nightclubs hired musicians like Louis Armstrong, apparently had time to kill.

Capone could read music and liked to play a banjo and a mandola, which is like a mandolin, only bigger. According to Mr Larsen, who is working on a documentary about Capone's influence on music in the 1920s and '30s, the gangster begged the warden for permission to form a small band. The warden relented, the inmates sent away for instruments, and Capone made music behind bars.

Enter Vincent Casey. As part of his training to become a Jesuit priest, Mr Casey would visit Alcatraz to offer spiritual counsel to prisoners in the 1930s. Mr Casey and Capone talked in the mobster's cell every Saturday for two years, becoming good friends, said Mr Casey's son, Mike Casey, a retired airline employee in Temecula, California.

The way Mr Larsen tells it, the gangster who supposedly orchestrated the 1929 St. Valentine's Day Massacre - in which his henchmen pulled machine guns from violin cases, incidentally - was a religious man. So the song might be about the Virgin Mary.

But Mr Larsen thinks it is more likely that the song was Capone's valentine to his wife, Mae, who stuck by him, even after he went to prison and suffered the effects of syphilis, the disease that led to his death in 1947.

The sheet music is inscribed, 'To my good friend Father Vin Casey with the best in all the world for a Merry Christmas always for you. Alphonse Capone.' Mr Casey took it home. Never ordained, Mr Casey married and before he died in 1960 showed the gift to his son, suggesting that it may have more than just sentimental value.

Capone's love of music was evident right up to the end of his life. In his research for a book about Capone, Chicago author Jonathan Eig found that even when Capone's mind was ravaged by syphilis and he was paranoid and delusional, he continued to play his mandola. -- AP