ATLANTA (AP) _ Sam Ketcham, the organ grinder expelled from Lenox Square after 29 years because he wasn't ''upscale'' enough, was back in the glitzy shopping mall for one night at an appearance sponsored by one of the stores.

Shoppers stood in line Thursday night to sign a petition calling on the mall to bring back Ketcham, 72, and his monkeys.

Ketcham's son, Robert, and a monkey entertained shoppers and collected change at the Social Expressions card store while the elder Ketcham, who said he did not feel well, watched.

''This guy's an institution,'' said store owner Albert D. Maslia. ''Lenox has always been upscale. But upscale's got nothing to do with a monkey.''

The mall cited its toney image in evicting Ketcham in July. He had worked crowds at the mall since it opened in 1959.

A spokesman for the mall said Thursday that it is standing by the decision.