Hello Jeremy and others! When I today booted into Leopard and launched X11, it was the MacPorts package xorg-server-devel @1.17.1_0 that provided the X server. The clients looked different, instead of brown the window decoration was green. And gkrellm and GNU Emacs 23.4 died. The mouse cursor was invisible although X11 had the focus and therefore was easy to quit. I then activated xorg-server-devel @1.17.0_0. With the same results. With xorg-server-devel @1.16.99.1_2 everything is OK. I have crash logs: -rw------- 1 pete admin 21182 14. Feb 19:02 emacs-23.4_2015-02-14-190207_Leopard.crash -rw------- 1 pete admin 23320 14. Feb 19:01 gkrellm_2015-02-14-190103_Leopard.crash -rw------- 1 pete admin 21180 14. Feb 18:56 emacs-23.4_2015-02-14-185620_Leopard.crash -rw------- 1 pete admin 23318 14. Feb 18:55 gkrellm_2015-02-14-185514_Leopard.crash -rw------- 1 pete admin 21180 14. Feb 18:51 emacs-23.4_2015-02-14-185108_Leopard.crash -rw------- 1 pete admin 23318 14. Feb 18:51 gkrellm_2015-02-14-185022_Leopard.crash -- Greetings Pete The best way to accelerate a PC is 9.8 m/s²