I too am affected by this bug. The workaround suggested by stpg works to an extent, however the software render is used instead of the appropriate hardware driver.
err:winediag:X11DRV_WineGL_InitOpenglInfo The Mesa OpenGL driver is using software rendering, most likely your OpenGL drivers haven't been installed correctly
direct rendering: Yes
OpenGL vendor string: X.Org
OpenGL renderer string: Gallium 0.4 on AMD SUMO
OpenGL version string: 2.1 Mesa 7.11
OpenGL shading language version string: 1.20
I too am affected by this bug. The workaround suggested by stpg works to an extent, however the software render is used instead of the appropriate hardware driver.
err:winediag: X11DRV_ WineGL_ InitOpenglInfo The Mesa OpenGL driver is using software rendering, most likely your OpenGL drivers haven't been installed correctly
direct rendering: Yes
OpenGL vendor string: X.Org
OpenGL renderer string: Gallium 0.4 on AMD SUMO
OpenGL version string: 2.1 Mesa 7.11
OpenGL shading language version string: 1.20