Maryland's Court of Special Appeals yesterday blocked a Prince George's County Circuit Court order placing the county's jail system under court control.

The decision by the appeals court to delay the takeover until a full appeal of Judge James M. Rea's order can be heard raised the possibility that 120 jail guards and other corrections employes might walk off the job again and rejoin the 1,400 county employes still on strike.

They were still on the job early today after negotiators for the public employes union and the county met for six hours without success. Negotiatiors said after the session broke up at 1 a.m. that they were far apart and thatthe guards' future employment status with the county is a key issue in efforts to end the 10-day strike. Negotiations are to resum this afternoon.

The guards, whose walkout Aug. 12 began the strike, agreed to return to work Monday after Rea ordered them back and warned County Executive Lawrence J. Hogan not to take any reprisals against them.

In his ruling, Rea also placed the operation of the jail under a court-appointed trustee on the grounds that Hogan had been unable to resolve the protracted dispute with the striking American Federation of State, County and Municipal Employees.

The trustee, George Gifford, would be paid by the county, to oversee the operationsof the county jail and Corrections Department until the county and union are able to resolve their contract differences.

Rea also ordered the county to pay the jail guards 9.7 percent cost-of-living increase that non-union employes were given when the labor dispute with AFSMCE first began 18 months ago.

County attorneys immediately appealed Rea's order and took the additional step of asking the appeals court to block its enforcement because, the lawyers said, the judge had improperly exceeded his authority.

The three appeals court judges who heard the case yesterday gave no explanation for blocking Rea's decision.

During the hearing, Chief Judge Richard P. Gilbert told the two sides that they should ask the state's highest court, the Court of Appeals, to hear the full appeal of Rea's order and a previous Circuit Court ruling the county has appealed that found Hogan guilty of violating labor laws.

An appeal of a Circuit Court decision normally goes to the Court of Special Appeals, but the state's highest court could choose to hear the case. No date has been set for either appeal.Both courts are adjourned until after Labor Day.

Hogan said the delay will allow the county "to rationally resolve the situation instead of through the courts."

He added that "no precipitous actions will be taken" against any of the 80 jail guards who went out on strike and then defied a court injunction ordering them to returnto work. All of those guards returned to work Monday because of Rea's order.

County Attorney Robert Ostrom saidyesterday that Arnette W. Gaston, director of the Corrections Department, will be considering on a case-by-case basis whether to fire or otherwise discipline the jail guards who went on strike last week.

Attorneys for AFSCME and union leaders reacted with surprise yesterday to the appeals court ruling blocking the enforcement of Rea's order. The lawyers had aruged in court yesterday that Rea's decision had restored order to the jail system and without it the jail would return to last week's chaos while the two sides continued to argue over a contract.

The jail erupted in rioting during the strike's first hours and the county called in state police to restore order in the facility. The state police left early this week after the county began hiring new guards and the strikers returned to work.