How to scale a object to 120%?

I’ve got an object by:

planeWall = new THREE.Mesh(new THREE.PlaneGeometry(10,5,1,1), material);

Then I want to make it bigger, say, 20% so I tried:

planeWall.geometry = new THREE.PlaneGeometry(12,6,1,1);

but failed,debugger says:

TypeError: Cannot read property 'radius' of null

Is there anyone has some experience for this?

[jbovatsek]

planeWall.scale.set(12,6,1);

[WestLangley]

@tmdeft three.js does not support negative scale factors. See http://stackoverflow.com/search?q=[three.js]+support+negative+scale