Hi,
I can confirm the the bug is still present in kernel 3.11-2-amd64 but it works fine in kernel 3.12-rc7-amd64. I haven't had a chance to test 3.12-trunk-amd64 (which is the only 3.12 available in my repositories) because it fails to compile the proprietary ATI fglrx kernel module and I would have to reconfigure xorg.
Thanks,
Paolo