[jitter] tut 41 : Is my |ATI Mobility Radeon 9600| the problem ?

Hello,

I'm working on the tutorial 41 : Shaders
But I can't read the mat.dirperpixel.jxs shader.

Is my card the problem ?
I'm on OSX with Max 4.6.3 and jitter 1.6.3

________________________Max____________________________________
jit.gl.render: building GL on pwindow "shctx"...
? error: -- START GLSL INFO LOG: vp --
ERROR: 0:26: 'assign' :  cannot convert from '4-component vector of float' to 'varying 3-component vector of float'
? error: -- END GLSL INFO LOG: vp --
? error: jit.gl.shader: GLSL program failed to compile.
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