Jack Sparrow: Who makes all these?
Will Turner: I do. And I practice with them... Three hours a day.
Jack Sparrow: You need to get yourself a girl, mate. Or perhaps the reason you practice three hours a day is that you've already found one and are otherwise incapable of wooing said strumpet. You're not a eunuch, are you?
Just as Jack says, "On deck, you scabrous dogs," to the very left edge of the screen over Jack's shoulder is a grip crew member with a tan cowboy hat, white short sleeve tee shirt and sunglasses, just standing there looking out to sea.
The bit where Will impersonates Jack was devised by Orlando Bloom (Will), who asked the producer if he could put it in the movie.