Samsung X20 suspends again after resume when using FN+ESC-Keykombo

Whenever I suspend my Samsung X20 Laptop using the FN+ESC-Keycombo (which is the default-behaviour), and then wake it up using the Powerbutton, the laptop immediately suspends again. After the second resume it stays on.

This seems to be related either to acpi-support or gnome-power-manager and it only happens, when I'm under KDE with Power-Manager enabled. When I use Power-Manager Right-Click->Suspend everything works fine. When I kill Power-Manager and use the Key-Combo everything is fine as well.

The solution from https://bugs.launchpad.net/ubuntu/+source/acpi-support/+bug/14718 (re-installing acpi-support) didn't help, neither did https://bugs.launchpad.net/ubuntu/+source/gnome-power-manager/+bug/28045 .

Versions:
acpi-support-0.95
powermanagement-interface-0.3.15
kubuntu-feisty 7.04