Go to the scene where they are at the sarlac pit and the big fight breaks out between the good guys and all of Jabba's guards. There is one part where Chewie has just untied Han. Bobba Fett is standing behind them. Chewie says something in wookie speech, and Han exclaims "Bobba Fett?!" (one assumes that Chewie has just informed him that Bobba Fett is standing behind him). It then cuts to a shot of Fett raising his gun to shoot at Luke. As he does this, listen very hard and you will hear Han say "Bobba Fett?!" again in the background. We heard you the first time!