Native method not found: com.unity3d.player.UnityPlayer.UnitySendMessage

[otsuga]

First thanks for this asset!

When i receive a message when the application is closed im getting this error on logcat.

E/AndroidRuntime(3480): Caused by: java.lang.UnsatisfiedLinkError: Native method not found: com.unity3d.player.UnityPlayer.UnitySendMessage:(Ljava/lang/String;Ljava/lang/String;Ljava/lang/String;) 08-08 16:20:45.005: E/AndroidRuntime(3480): at com.kskkbys.unitygcmplugin.Util.sendMessage(Util.java:22) 08-08 16:20:45.005: E/AndroidRuntime(3480): at com.kskkbys.unitygcmplugin.Util.sendMessage(Util.java:22) 08-08 16:20:45.005: E/AndroidRuntime(3480): at com.kskkbys.unitygcmplugin.UnityGCMIntentService.onMessage(UnityGCMIntentService.java:50)