Waiting for it to be packaged, I just fixed it on my machine with this: http://www.rktmb.org/post/2013/02/06/arandr-quick-fix-invalid-literal-for-int-with-base-10
It's about changing one line, firing the int() cast. Caution: very dirty, just a quick workaround for those in a hurry. -- RMA.
