https://bugs.freedesktop.org/show_bug.cgi?id=36318
--- Comment #3 from Alexandre Demers alexandre.f.demers@gmail.com 2011-04-17 09:22:02 PDT --- If ldd confirms you are using the good library, have a look at the following bug: https://bugs.freedesktop.org/show_bug.cgi?id=36282
It may explain the problem. Otherwise, watchout for Natty, things are a real mess because drivers are now installed under the multiarch folder, but the dev files are installed in a different folder. So if you just compiled and installed like you were doing in previous Ubuntu version, you will end up in a dead end. I had to work a bit to figure everything out.