One of the series DePatie-Freleng did for United Artists' theatrical release was "Tijuana Toads", which featured two frogs (Toro and Pancho) who spoke with stereotypical Mexican accent. Here's one of the shorts:
Around the time this came out there was a controversy over a food mascot Frito Bandito from Mexican activists which led to the character fading away. However, since the Toads shorts were theatrically released (and I might add that they were made from 1969 to 1972, long after theatrical cartoons were no longer in demand) they were able to get away with it.
Well, not for long. They later showed up on network television (on NBC as part of their Saturday morning Pink Panther block) but DFE had to redub their voices to make them "Texas Toads". The dubbed version didn't seem to last, since the original theatrical version eventually did show up on syndication in the 1980s.
Was the redubbing justified? Is the Mexican accents that offensive? If anyone has anything to say, feel free.