Fixed bug 2157 - Caps Lock key produces key down & key up events while key is still pressed. Tim McDaniel Using checkkeys test app: * Press and hold Caps Lock key. * checkkeys reports a CapsLock key pressed event and a CapsLock key released event. * Release Caps Lock key. * checkkeys reports no further events. This patch fixes OSX Caps Lock up/down event detection by installing a HID callback.