According to tv.com:
In the Mexican version of the Simpsons episode 242 Pygomoelian, the Doctor that Moe replaced in the soap opera said 'They can't replace me! I played the role of Doctor (??) and the voice of Ranma for the last (?) years!'. This was a play on the fact that the guy playing the voice of the Doctor in this episode was the same guy that made the voice of Ranma Saotome, lead character of an anime named Ranma 1/2 which played in Mexico for a while before this episode was made.
The above picture is a screen grab from the episode mentioned of the doctor that Moe replaced.