how to tile a texture

[vDeonne]

I tried to tile the 'ground' by texturing using the code below. Rather than tile, however, the texture image is enlarged to texture the ground -- with no repeat. What code can I use to ensure that the texture image tiles rather than stretches?

ground = viz.add('tut_ground.wrl')
ground.setPosition(0,0,0)
ground.collidePlane()
leaves = viz.add('fall-leaves.jpg')
leaves.wrap(viz.WRAP_S,viz.REPEAT)
leaves.wrap(viz.WRAP_T,viz.REPEAT)
ground.texture(leaves)