I have some problems with the armature collision. I know that this type of collision is bugged. So, I want an alternative collision.
I’m trying to do this with emptys. But there are some problems, for example:
I don’t know how can I do the character stop in the jumping. He jumps and pass trought the other mesh. How can I make he stop to go up?
English isn’t my native laguage, so I’ll translate the other problems before post them here.

He jumps and pass trought the other mesh. How can I make he stop to go up?

You can use a property to stop the force from being applied. The key starts the force and also changes a property. A property sensor stops the force and resets the property. Another method is to use a collision sensor with the ground with the key. So it only applies force if the character is in contact with the ground. He shouldn’t be passing through a mesh. I parent the armature to an invisible cylinder myself, and then control the cylinder and the armature. You have to make sure that only one object has any collision if there is an armature involved. There’s a game reference here:

Uh… I don’t think you understood.
He jumps under a mesh, and his head pass troght his head. He can only jump if there is something under him (I used the Ray sensor). But this is not the problem, it is the first I said: he pass trought “floating” objects when he jumps.

If your armature has the movement logic bricks on it, look at it in wire mode. When you select it their should be a dotted sphere that shows up. That’s about the area of collision. If the sphere is smaller than your object, that’s why it’s going through meshes above it. You can try and change the radius so your character fits inside it.

A better idea would be to make an invisible cube or cylinder about the same size of the character and parent the armature to that. You can then control all the movement with the cube. If you select the cube and the armature at the same time, you can have one logic brick telling the cube to move/jump/whatever, and also link it to the armature and have it play the walk/jump animation.

The first idea is bugged, but the second looks fine. I’ll try it.