More on this, you need to restart acpid after every suspend/resume cycle. Noticed this in the X log:
When X starts up: (II) Open ACPI successful (/var/run/acpid.socket) After restarting acpid: (WW) Open ACPI failed (/var/run/acpid.socket) (Connection refused) After resuming: (II) Open ACPI successful (/var/run/acpid.socket) It seems that it doesn't work while it has a connection to the acpid socket. Running acpi_listen from another machine. The LCD moves from the off state to the blanked state whenever a 'battery' event appears. eg: battery BAT1 00000080 00000001 battery BAT2 00000080 00000001 -- LCD panel won't stay powered off https://launchpad.net/bugs/55648 -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs