I am running into the issue where XUngrabKey(AnyKey, AnyModifier) seem not to ungrab the keys, but with with many calls to XGrabKey it seem to work.
Here is what I am trying to do: I am trying to disable all the keybindings in metactity: "metacity-message disable-keybindings"
Metacity tries to ungrab all keys with just one call to XUngrabKey(), using AnyKey + AnyModifier, the code in DeletePassiveGrabFromList() seems to try to implement the desired behavior, the manpage of XUngrabKey() also says it works this way, so there seems to be a bug somewhere that prevents AnyKey/AnyModifier from matching individual key grabs from the list.
This is on Fedora 14 where we have xserver 1.9.4.
I diagnosed the same environment (XO-1.5) and found that metacity is not executing any X commands in response to that message, it just sets a local variable.
After extending metacity to actually call XUngrabKey(Any, Any) it is working fine - the key grabs get dropped.
This can probably be closed.
Closing then. Thanks.