Here's a tactic that was used in the 18th century to get sailors on the ship to eat sauerkraut, which contains vitamins that prevent scurvy, among other diseases (the typical shipboard diet consisted of dried bread and salted meat). Sailors originally refused to eat it, because they considered it unmasculine. So, when barrels of sauerkraut were packed onboard the ship, sailors were told that it was for officers only. During the day, officers ate sauerkraut with meals, while keeping the sailors away from it under the threat of punishment. However, when officers went to sleep, they left the barrels out in the open, as opposed to locking them somewhere. Sailors would then get up in the middle of the night, and sneak sauerkraut from the barrels by handfuls. Officers, in turn, pretended not to notice that barrels were being tampered with. In the end, the sailors got their vitamins, and the officers got the sailors to do what they originally balked at.
This is one of those situations where history can teach us a valuable lesson, and it goes back as far as Adam and Eve. Here's what you can do to get your kid to eat vegetables. Make a really great-looking vegetable dish or buy a veggie platter from a caterer, and tell your son that he's not supposed to touch it. Somehow, hype it up to make the dish look enticing. Give him a light but noticeable punishment when you see him do it (such as no coming into the kitchen for the next two hours). Unless he's very obedient, he might try to sneak pieces from it when you're not looking. And if you don't see him, act like you didn't notice anything. In the end, he'll eat the foods you want him to eat, because you're setting it up as a forbidden fruit.
Of course, if your son is wise to this tactic, then the previous paragraph is a moot point. In that case, have him drink of the V8 juices I mentioned in my last post. Or, as a last resort, buy a lot of salsa, and have your son eat it with chips (get the baked kind; they're healthier). USDA recognizes salsa as a vegetable, so it's better than nothing. Either way, good luck.