The best part in that movie is when Wilfred Brimley says "fuck" under his breath. I guess George was asleep in the editing room. Maybe he made the mistake of watching the movie.
Wookieepedia claims this was debunked.
Then again, it sure sounds like someone yells "Die F*cker!" in ROTJ as the super star destroyer crashes into the Death Star...
That's also not nearly as weird as the Ewoks having an english conversation about C3P0. The "die, ya fuckers" is a bit interpretive, but the english Ewoks was a genuine easter egg!