When opening an app which uses the compass sensor, I get the following messages on syslog:

Oct 24 10:30:59 (2011) sensord[648]: *WARNING* [../../core/nodebase.cpp:267:bool NodeBase::setIntervalRequest(int, unsigned int)]: Invalid interval requested for node 'compasschain' by session '24': 0
Oct 24 10:30:59 (2011) sensord[648]: *WARNING* [../../core/sensormanager.cpp:615:void SensorManager::sensorDataHandler(int)]: Failed to write data to socket.
Oct 24 10:30:59 (2011) sensord[648]: *WARNING* [../../core/sensormanager.cpp:615:void SensorManager::sensorDataHandler(int)]: Failed to write data to socket.

last messages repeated until I close the app.