Hmm.... It's listed as a GL 4.3 feature...........
http://cgit.freedesktop.org/mesa/mesa/tree/docs/GL3.txt
Phoronix: Intel Mesa Gets Another OpenGL 4.2 Feature
Chris Forbes has introduced support for Mesa and specifically Intel's DRI driver to support ARB_texture_storage_multisample, a feature that's been apart of core OpenGL since version 4.2...
http://www.phoronix.com/vr.php?view=MTMyOTI
Hmm.... It's listed as a GL 4.3 feature...........
http://cgit.freedesktop.org/mesa/mesa/tree/docs/GL3.txt