In gnome-screensaver/src/gs-listener-dbus.c there is a hard-coded(!) handler for the "coffee" button which instruct gnome-screensaver (i.e. itself) to lock the screen. Apparently, unrelated buttons are mapped by HAL to the "coffee" button. E.g. I have the problem with my Cherry CyMotion master linux keyboard, when I press the "Copy" key.
Launching "dbus-monitor --system" and pressing the button gives
signal sender=:1.12 -> dest=(null destination) serial=2054 path=/org/ freedesktop/ Hal/devices/ platform_ i8042_i8042_ KBD_port_ logicaldev_ input; interface= org.freedesktop .Hal.Device; member=Condition
string "ButtonPressed"
string "coffee"
In gnome-screensav er/src/ gs-listener- dbus.c there is a hard-coded(!) handler for the "coffee" button which instruct gnome-screensaver (i.e. itself) to lock the screen. Apparently, unrelated buttons are mapped by HAL to the "coffee" button. E.g. I have the problem with my Cherry CyMotion master linux keyboard, when I press the "Copy" key.