In my Android app I enable my specific app-search to be triggered via the search key in a number of my activities using this mechanism from the manifest
If you have a cyanogenmod based phone (e.g. jellytime for HTC DHD like me), the old behaviour is only a setting away:
Menu/Systemsettings/System/Hardware keys/Search/In-App-Search
But this change wasted quite some of my time for debugging my app and researching to find this solution. Needless to say I hate patents, especially ridiculous ones: obvious behaviour like an OS sending a hardware key event to an application can be patented???