matplotlib does not work with numpy > 0.9.8. I think a restriction should be put in the ebuild. This thread has some info: http://aspn.activestate.com/ASPN/Mail/Message/numpy-discussion/325073
matplotlib-0.87.5 works with numpy-1.0b5 and later.
I just bumped matplotlib to 0.87.7 which seems to compile with current ~arch numpy. I suspect the deps need to be tightened up here, but I cannot find any information on this in the matplotlib tarball and it looks like http://aspn.activestate.com/ASPN/Mail/Message/numpy-discussion/325073 is not the right url (it links to "Re: [JPython] JPython servlets"). Further information on what needs to be done here would be appreciated, so I do not have to resort to trying all possible combinations of numpy and matplotlib :)
matplotlib-0.87.7 is compatible with numpy-1.0 and later. Previous versions of matplotlib are not compatible with numpy-1.0.
bicatali: is this fixed with your commits?
now fixed.