Hardware skinning

Hi ,
I’m working on some proof of concept demo for my future project and I took a look on Xith3d.
I implemented a SMD format loader (i will commit it into the project if I clean the code) but there are a few things I am missing here…
I want to do hardware skinning and I read this article on Gamasutra:
http://www.gamasutra.com/features/20030325/fernando_05.shtml
I took a look at the VertexShader class and I saw that you can load the shader code and some arguments to your shader. What I don’t understand is how can I pass a whole array of bone matrixes to the shader (those declared uniform in the example).
Thanks in advance for your help

BR
G