@ micia: sorry for the late reply, but as we've solved this, i forgot to keep track of the post
answering your question about the pic flag, I haven't enabled/disabled any USE flag. Just installed mesa from portage with "emerge -1av mesa", and it worked.
I've thought trying to install it with default config first, and then try other flag enabling/disabling if default don't work... but that wasn't necessary
I'm glad to see that this is useful for someone else
I'm performing now a global update. After that i will install the entropy version of mesa and see if the problem persists. If it doesn't, then i will edit the main message to show everyone with this problem that upgrading mesa from entropy is the solution. But only if that works EDIT:
it seems that mesa 7.11 from entropy works just nicely. no need to use portage now.
Thanks a lot for your help on this micia
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