Until two weeks ago, Intelligent Tarref Allah, a 27-year-old Brooklyn native convicted of murder in 1995, was just a gang member in prison asking for special treatment. For years, New York State prison officials would not allow Mr. Allah — who is known to inmates and guards by his new legal first name, Intelligent, or Intel — to openly practice what he describes as his religion, central tenets of which encourage self-analysis, meditation and a black supremacist message. Mr. Allah is a Five Percenter, part of a black militant group that broke from the Nation of Islam in the 1960's....