aggresive behaviour when doorbell rings

Question
I have a 90 lb lab/terrier cross. When someone knocks or rings the doorbell, he goes ballistic. If we don't get to the door quickly he scratches at it in his excitement. He won't get out of the way when I open the door and obviously it is quite a daunting prospect for the person at the door to see this creature trying to get at them. When the door is opened he trys to rush out to greet the person. He has never actually bitten anyone however. He jumps up but not on them. Help please!

Answer
Well what you do is when he jumps up on someone,tell them to knee him in the chest and say 'off' and keep on doing that until he doesn't jump anymore,it won't hurt him,but he could really hurt someone and you could wind up in court

also when someone is at the door use a choke chain and a leash and make him sit and stay before opening the door(you can tell the person to wait a minute,you are calming the dog down)