Shadow Mapping with glsl and mesa

[smani]

Hello,
I am struggling get shadow mapping with shaders working with glsl. The test code I am using (see attachment), based on fabiensanglard.net/shadowmapping/index.php, works fine with nvidia drivers, but when using mesa something with the texture access in the fragment shader seems to go wrong, resulting in random noise. Does anyone by any chance have a working sample code?

Thanks!
smani

glxinfo:
OpenGL vendor string: Tungsten Graphics, Inc
OpenGL renderer string: Mesa DRI Mobile Intel® GM45 Express Chipset GEM 20100330 DEVELOPMENT
OpenGL version string: 2.1 Mesa 7.9
OpenGL shading language version string: 1.20