installing opengl library

Hello everybody,
I am using the beagleboard with the angstrom demo distribution for
Since I couldn't get the graphical accelerator opengl drivers yet, I
decided to start working with SW rendering for the moment (not using
the graphic accelerator).
Did someone have tried that?
What library shall I download and install in order to have a rendering
in SW with opengl ES APIs (either 1.1 or 2.0)?
Thanks for your help.