It sounds like this behavior has been going on for awhile, you also haven't mentioned once whether or not he's been to a professional trainer in his life. Honestly, it sounds like you haven't done anything to address the behavior, and instead are trying to rehome him.
If this has been going on for awhile, it should have been addressed immediately. Please know that no shelter will even consider putting a dog with those issues out on an adoption floor, and his best bet is going to a trainer that has experience with aggressive dogs.
We see a lot of these behaviors at the shelter in little dogs, because they're consistently allowed to get away with them.
Please correct me if I'm wrong, and give us more information on your boy. If he's been to a trainer, what age this behavior started, etc.
Last edited by BMoore; 10-29-2011 at 02:20 PM.