Generally the best way of stopping a dog jumping is to prevent the dog being rewarded for doing it. That, of course, is easiest when the person being jumped on is yourself (since you control your own reactions). The trick to stopping jumping on others is actually the same - to control their reactions, and hence the reward (or lack of it) that the dog derives from doing it.
Sooo - how are people reacting? Do they shriek? Pet the dog? Give the dog any attention at all? They probably do, and by doing so are rewarding and reinforcing the jumping behaviour. And as long as that continues, the dog isn't going to be deterred from jumping, no matter what you do.
I know its a difficult thing to control the behaviour and reactions of every person that comes into your home, or into contact with your dog. But if you can recruit just a few of them to help you train the dog, you've got a fighting chance of success.
I would suggest a few things. In the first instance, if someone (anyone) is coming over, control the dog with a leash. Do not allow him the freedom to jump up and be rewarded for doing so (no form of punishment will offset the reward - so avoid rewarding him by preventing the behaviour). That rule should be applied especially in the case of anyone whom you haven't recruited to help with his training, since their reward/reaction will undermine any useful training you do.
Then - if you can get a willing volunteer or two, the thing to do is to brief them carefully about how to greet the dog. They should pay the dog no attention - that even means no eye contact, let alone speaking to him or petting him - unless he is calm and sitting down. The point here is that they should NOT reward anything but the calm sitting dog, and that dog should be amply rewarded by attention. Just like little kids (and even adults) dogs respond to the thing that gets them rewards - so be sure that he is only rewarded for the good calm behaviour. If the dog is excited, pulling at his leash, trying to jump up, or even successfully jumping up, they should turn away and ignore him. He does not exist until such time as he's sitting nice and politely, then he can have plenty attention.
So, with person briefed to respond ONLY when the dog is calm and quiet, you should have them come to your door and ring the bell. PUT the dog on a leash - you need to be able to prevent him jumping. When you get to the door, ask him to sit and stand on his leash (so he can't jump). Leave plenty room for the visitor to enter without having to get within range of the dog
They should pay him no attention, just keep talking to you, until the dog calms down and sits still. When he gives a bit of a puff or sigh and sits down - THEN he can be acknowleged by the guest (that is, rewarded for sitting down quietly). Repeat this several times, and on as many occassions as it takes for him to start calming down quickly. If you can get more than one person to be your guinea pig, that's even better (providing they take the ignoring thing seriously).
As time goes on, you should be able to progress to letting the dog loose after a few minutes. And eventually to answering the door without him leashed. If at any time there is a lapse and he jumps up, the person should cross their arms, turn away and ignore the jumping dog. If that doesn't work, put the dog out of the room (so he's not rewarded) and bring him back later on leash.
None of the above is the easiest thing in the world to get into the dog's head, and it's likely there will be lapses. Jumping up is, after all, a natural canine behaviour. We're asking them to go against that instinct in not jumping for attention - so the only way to really get that ingrained is through a lot of practice and absolute control of his rewards (that is, don't let him be rewarded for jumping - and just as importantly, make sure he IS rewarded for the behaviour you'd prefer from him).
We'll keep on her! It would however be easier if everyone in the neighborhood didn't adore her so much!