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Seems you use new svn trunk. Check the tutorial 10 in there (in examples folder), but basically it's now 2 functions.
With getVertexShaderConstantID you get a register id for the shader constant. And there's a new setVertexShaderConstant which takes that id instead of a name. Note that the old solution will still work for now, it's just slower because it's using constantly string-comparisons in rendering which is rather slow while working with id's is a lot faster.