java.lang.ClassCastException when using proguard

[bangive]

I enable proguard and install app on device using the following command:
gradlew android:installRelease android:run
I have this error from adb log:
E/AndroidRuntime( 8800): java.lang.ClassCastException: com.badlogic.gdx.utils.JsonValue cannot be cast to com.uwsoft.editor.renderer.data.SceneVO E/AndroidRuntime( 8800): at com.uwsoft.editor.renderer.resources.ResourceManager.initAllResources(SourceFile:96) E/AndroidRuntime( 8800): at com.uwsoft.editor.renderer.SceneLoader.<init>(SourceFile:63) E/AndroidRuntime( 8800): at com.example.mygame.r.create(SourceFile:15) E/AndroidRuntime( 8800): at com.badlogic.gdx.backends.android.AndroidGraphics.onSurfaceChanged(SourceFile:280) E/AndroidRuntime( 8800): at android.opengl.GLSurfaceView$GLThread.guardedRun(GLSurfaceView.java:1550) E/AndroidRuntime( 8800): at android.opengl.GLSurfaceView$GLThread.run(GLSurfaceView.java:1278)

[azakhary]

You should make sure the VO classes are all excluded from progurad. mark them as "keep" in proguard.cfg. It's about everyjthing in com.uwsoft.editor.renderer.data.**