Arnett Gaston, Department of Corrections director for Prince George's County, speaking at a community meeting this week shifted an earlier position and said he was "shocked" to learn that sexual assaults frequently take place in the county jail he runs and that he now believes there is a problem there.

Gaston, speaking of a Washington Post series published last fall that detailed numerous sexual assaults in the county's jail, refused to speculate on how widespread the problem might be. "I don't feel that numbers are important," he said. "I feel that there is a problem--I'd be foolish to believe otherwise. I'm not going to focus on how often or how little assaults occur . I'm going to focus on eliminating them ."

Gaston's comments, nearly identical to views expressed by newly elected County Executive Parris Glendening in recent months, marks a change from the stance Gaston took last fall when the series first appeared. Guards and inmates had estimated that rapes and sexual assaults occur about a dozen times a week in the jail. In response to information about specific cases, Gaston said then that he did not believe the rapes had occurred.

"You have a statement by one person with a history of bizarre behavior corroborated by another person with a history of bizarre behavior. What does that prove?" Gaston was quoted as saying. "I have no evidence that there are unreported rapes in this jail."

Gaston's more recent remarks, made after a speech he gave at a meeting of a Chillum-based community group Wednesday night, come near a spring deadline when Glendening will decide whether to make changes in key departmental positions.

Glendening said yesterday that he would make his decision on Gaston in about two weeks. "Public comment at this time would be unproductive," he said.

Privately, according to sources close to Glendening, the county executive has been troubled by the way Gaston has responded publicly to criticism about the jail. On the other hand, according to these sources, Glendening does not want to criticize Gaston unfairly for problems that may have resulted from a lack of support by the previous executive, Republican Lawrence J. Hogan. Glendening is also sensitive to criticism that might result from firing Gaston, the county's highest-paid black department head.

"Gaston isn't painting this as a black issue; he's been very professional about that," said a high-level Glendening associate. "But you have to be aware of it as part of the universe of concerns."

Gaston was invited to Wednesday night's meeting by Voters In Contact, a predominantly black community group headed by Democratic Central Committee member James Blackistone. Blackistone, a longtime Chillum community activist, said he invited Gaston to speak at the meeting to give members a chance to learn about law enforcement issues.

But, Blackistone said, he also wanted to give Gaston some community support. ". . . He's more or less on the spot," Blackistone said. "I just wanted to give him a chance to speak . . . . I just hope that no attempt will be made to remove him."