I used google.map api to develop a project which works well on android 2.1. But when I run the same project on android 2.2, it encountered some errors. The shown errors are " -- AndroidRuntime FATAL EXCEPTION:main -- AndroidRuntime java.lang.NoClassDefFoundError:android.net.NetworkConnectivityListener -- AndroidRuntime at com.google.android.maps.MapActivity.onCreate(MapActivity.java:199) " I don't know where is the problem? Can anyone help me? I will apreciate it very much!