EAST MEADOW - Inmates at the Nassau County Jail claim conditions at the facility are inhumane and illegal, and supporters staged a protest today on the steps of the county executive building. Prisoners have a long list of complaints about the jail, many of them relating to insufficient medical treatment. Five inmates have died at the prison in the past year and critics say poor medical and mental health care may have been factors. Back in 1990, Nassau officials came up with a plan to deal with problems at the jail. The county approved the formation of a visitors board, a committee of volunteers to hear grievances from inmates. Yet more than 20 years later, the oversight board has never been formed. Nassau County Sheriff Michael Sposato said his department "is meeting its obligations, including the provision of quality comprehensive health and mental services." He says the sheriff's department adequately handles complaints and suggested there's no need for a visitors board.The local chapter of the American Civil Liberties Union (ACLU) says it constantly hears complaints from prisoners. Members of the group protested today on the steps of the county executive building to call for the formation of the oversight board.