Same problem to me with Ubuntu 7.10. Before the update from Feisty everything worked like a charm, but immediately after the update i can write the wakeup time a thousand times to /proc/acpi/alarm, use or don't use the poweroff - kernel, the machine sleeps forever.
@Leann:
Even the new kernel from hardy did not work - i tested it exactly the way you described.
Same problem to me with Ubuntu 7.10. Before the update from Feisty everything worked like a charm, but immediately after the update i can write the wakeup time a thousand times to /proc/acpi/alarm, use or don't use the poweroff - kernel, the machine sleeps forever.
@Leann:
Even the new kernel from hardy did not work - i tested it exactly the way you described.