50 Cent has a great sense of humor -- just listen to the ad libs on his dis records. But when it comes to other people trying to profit from his name, he's not laughing. The rapper sued Taco Bell on Wednesday (July 23) for making him an unauthorized spokesman for the chain in a recent ad campaign, Reuters reports.

The news organization obtained the legal papers, filed in Manhattan federal court, in which 50 and his lawyers allege that the restaurant chain engaged in some unjust promotion. Taco Bell released a letter addressed to 50 in which the company suggested he change his name for a day to "79 Cent," "89 Cent" or "99 Cent," which are the prices of certain items on Taco Bell's menu.

"We know that you adopted the name 50 Cent years ago as a metaphor for change. We at Taco Bell are also huge advocates for change. We encourage you to 'Think Outside the Bun' and hope you accept our offer."

Fif wasn't feeling that at all.

"They crazy, man," 50 told radio personality Angie Martinez in June. "They sent a memo out. I don't wanna talk about it. We gonna take legal action. ... I guess they did that for promotional purposes. It's not good that they did that. They didn't have to do that.

"It gets uncomfortable at some point," he added about people trying to capitalize off his fame. "Especially when corporations do it to you. ... Like you gonna go to the store and beef with the kid at the counter."

According to Reuters, the lawsuit alleges that "many customers believed that 50 Cent had agreed to endorse Taco Bell's products. Indeed, postings on numerous Internet 'blogs' castigated 50 Cent for 'selling out' by his apparent endorsement of Taco Bell.

"Without seeking or obtaining Jackson's authorization, defendant Taco Bell made him the star and focus of its nationwide advertising campaign by using his name, persona and trademark to promote Taco Bell's business and products," the documents also accuse.

According to The Associated Press, 50 Cent lawyer Peter D. Raymond said the rapper didn't find out about the letter or the ad campaign until he saw a news report about it. Raymond also said 50 is seeking $4 million in damages.

Taco Bell Corporation spokesman Rob Poetsch has issued a statement that reads: "We made a good faith, charitable offer to 50 Cent to change his name to either 79, 89 or 99 Cent for one day by rapping his order at a Taco Bell, and we would have been very pleased to make [a] $10,000 donation to the charity of his choice."

[This story was originally published at 9:23 pm E.T. on 07.23.2008]