Rose Rock, the mother of comedian Chris Rock, claims she was racially discriminated against when she was seated but ignored for a half hour at a Cracker Barrel restaurant along the South Carolina coast.

Rock said Tuesday she planned to sue the Lebanon, Tenn.-based company. A Cracker Barrel spokeswoman said the restaurant chain was investigating and taking the complaint "very seriously."

Cracker Barrel has in the past faced numerous lawsuits and a federal inquiry over complaints of refusing to serve black customers, discriminating against minority workers and firing gay employees. The company has taken steps to rebuild its folksy image and reach out to minorities.

Rock, who is from Georgetown, said she and her 21-year-old daughter were the only blacks at the chain's Murrells Inlet restaurant in April. She said when she asked the manager about the delay she was told they could have a free meal.

"He never called over the waitresses and asked, `Why did these people sit here for a half hour without service?'" she said. "The only thing he said was we could have a free meal and neither of us wanted to eat."

Cracker Barrel spokeswoman Julie Davis said the company doesn't "tolerate any form of discrimination."

"It has always been a violation of our policies and procedures and it is neither condoned nor allowed," she said. "We do not allow the type of behavior you are describing," Davis said.

Rock said she contacted the South Carolina Human Affairs Commission and was told her complaint would be handled, but "nothing ever happened."

The head of the commission, Jesse Washington, said Tuesday that after initial discussions, the complaint was finalized Aug. 7 and his agency also was investigating. He would not comment on the complaint.

"We get thousands of charges coming through here in the course of a year," he said. "It's not out of line — the time frame on this. It is being investigated and we will be in touch with her when we have a report."

The Rev. Al Sharpton will join Rock on Wednesday in South Carolina to announce that Sharpton's Action Network will finance the planned lawsuit.

"I'm getting reports from all over the country about Cracker Barrel," Sharpton said from New York on Tuesday.

He also said state officials are slow to act on such complaints.

"When people are talking about there is no more discrimination, a lot of it is because they are not following this stuff up," Sharpton said.

Cracker Barrel, established in 1969, operates 547 restaurants in 41 states, according to the company's Web site.

Georgetown is about 60 miles northeast of Charleston.