Okay, I'm pretty sure someone has covered this on the Hunter forums, but I only lurk here from time to time, and haven't seen it mentioned before, although I have seen the problem mentioned.
As with many people who have boars, my little piggy Rancid is my pride and joy. A very smelly pride and joy, since he is a plagued swine. I tamed him at 60, surprised that he'd be so close to Undead, yet tameable. I kept him all the way to 70, not replacing him with something newer. Yes, I am one of those people who gets sentimetal over an in-game pet. All the way to 70, I didn't have a problem- except occasionally, when I was trapping mobs. Then, inexplicably, Rancid would decide to give the trapped mob a love tap before running back to his targetted mob- thus releasing the trapped mob. I almost never noticed it when soloing, but whenever I was in a group, he would do it at least once. It was frustrating, but I could live with it.
Recently, I saw a couple of posts on various forums mentioning the same problem. The solution the people came up with was simple- get a different pet. I didn't care too much for that, but decided to tame a Ripfang Lynx from Netherstorm. I went and did the deed without too much effort, but I wasn't happy with the result. The new pet was surly and moody, and was eating me out of house and home. I wasn't looking forward to a long stint of getting it used to me, having to feed it much more often than even Rancid needed, and have it go into frequent sulks for who-knows-how-long. So, I released it, and it pranced happily away.
I took poor Rancid out of the stables and went to the pet trainer in Ironforge, asking for some alternative to having to euthanise my good friend. Luckily, I was able to get him to un-learn everything he had been taught, and retrained him in new skills- one of which was Dash! We are now a happy team again, running through the wilds of Outlands and clearing a path wherever we venture.
The moral of the story: don't give up on your boar when he (or she) Charges rampantly at every mob- drop Charge and get Dash. The only thing you really lose is the stun ability, but the boar will start running faster earlier, and for longer distances.