I'm using XInput 2.1/2.2 and the problem is that the delivery of raw events is prevented while the mouse-button is pressed on the client's window. The server activates an implicit passive grab when I press the button. The bug here is that the grab window is different to the root window.
http://patchwork.freedesktop.org/patch/11769/
Thank you for the patch, Peter! I can't manage to compile the X server to test it. But I am quite sure the patch does what it should do. So everyone feel free to test it.
commit 4e13dd90144dde47550aceea4db4b4329e531279 Author: Peter Hutterer <peter.hutterer@who-t.net> Date: Wed Aug 22 10:34:07 2012 +1000 dix: don't filter RawEvents if the grab window is not the root window (#53897)
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