The problem is solved in kernel 2.6.39-0. This Kernel isn't stable at this time but works fine.. An how-to: http://blog.lome.pl/blog/ubuntu-11-4-black-screen-problem-solved/
** Changed in: linux (Ubuntu) Status: Incomplete => Fix Released -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/777944 Title: Plugging external monitor causes kernel hardlock -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs