Had the same problem, installed gallium drivers as was suggested in this discussion http://getsatisfaction.com/mojang/topics/anything_but_tiny_draw_distance_crashes_minecraft_using_mesa_radeon_drivers_on_x11
How to install: http://phoronix.com/forums/showthread.php?24195-Help-wanted-instaling-Gallium3D-Ubuntu-10.04-ATI-x1400 Not a fix but a workaround... -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/656045 Title: [r300] Minecraft crashes, fairly randomly [SIGSEGV (0xb)] -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs