I just realized my thread went away with the server change. From IMDb:

Mexican actor Gael Garcia Bernal refused to attend Sunday's 77th Academy Awards - because Antonio Banderas replaced singer Jorge Drexler to perform at the ceremony. The Motorcycle Diaries star was horrified when he learned that Uruguay's Drexler wouldn't be able to perform his own "Al Otro Lado Del Rio" on the show "for commercial reasons" and was replaced by Banderas and Carlos Santana. But Bernal was thrilled when Drexler scooped an Oscar for the song and made a point of singing some of the song instead of making a speech. He says, "At the time his song is being honored, all a sudden, that's the moment he does not exist? It was impossible for me to be there as part of the film. I didn't want to pretend the song was not part of it; that would have been like an act of murder in the family. And secondly, the film and the song are about respecting people's identity."