more examples of AR?

[Darkmax]

i was trying to get work the artoolkit plugin but i dont know how to have another window in my virtual application with AR.

this is my code:
[CODE
]ar = viz.add('artoolkit.dle')

# Create a new window in the down left of the main window
DownLeftWindow = viz.addWindow(pos=(0,0),size=(0.2,0.2))
DownLeftWindow.visible(0,viz.SCREEN)

video = viz.add('VideoCamera.dle')
cam = video.addWebcam()

ar.addCamera(cam,param=None,flipVertical=False,thr esh=None,globalScale=None,window=DownLeftWindow)
[/CODE]

but this error throws me:
Warning: TextureRectangle::apply(..) failed, texture rectangle is not support by your OpenGL drivers.

i dont know how to resolve my error.