Could you try with libgl1-mesa-glx 6.5.2-3 currently in experimental? The FIXME code seems to still be there, but maybe something else has been added to work around the problem...
If it still fails, it should be reported upstream. Brice
- Bug#415292: libgl1-mesa-glx: assertion failure in li... Brice Goglin
- Bug#415292: libgl1-mesa-glx: assertion failure ... Nikita V. Youshchenko
- Bug#415292: libgl1-mesa-glx: assertion fail... Julien Cristau
- Bug#415292: libgl1-mesa-glx: assertion ... Nikita V. Youshchenko
