O'Neal avoided jail time last month (Aug11) after he pleaded no contest to two felony counts, including heroin and firearms possession - because the judge sentencing him felt he'd be better served in rehab.
He was also placed on five years' probation but warned he faced a three-year state prison sentence if he violated the court's terms.
On Thursday (15Sep11), his probation was revoked and Redmond has been taken into custody after confessing to using drugs in rehab.
Prosecutors claim O'Neal called a dealer from a pay phone and had methamphetamine brought to him at the facility.
He will return to court on 7 October (11) for sentencing.
Redmond O'Neal was jailed in 2009 after he was found in possession of heroin during a routine security check at the Pitchess Detention Center, California. He was behind bars when his mother died in June, 2009.