Comment 4 for bug 851947

It absolutely should not. The *native* nvidia and mesa drivers cooperate correctly - the newly introduced /usr/lib32/libGL.so.1 does *not* follow the same (carefully designed and tested) method of selecting the GL driver via update-alternatives.

I think you should revert your recent changes to mesa handling in ia32-libs. We are not ever going to have fully working 32-bit support for mesa + nvidia GL via ia32-libs, so we might as well stick with the previous known set of bugs - which also resulted in smaller ia32-libs package anyway.