Google Push Notification c2dm from Android 2.3 to 5.x INSTALL_FAILED_DUPLICATE_PERMISSION perm=com.google.android.c2dm.permission.RECEIVE

Question

I got a strange problem: to make push possible also on 2.3 devices (even app-installable) you need to declare:

<permission android:name="com.google.android.c2dm.permission.RECEIVE"/>

and on higher api levels you have to add:

<uses-permission android:name="com.google.android.c2dm.permission.RECEIVE"/>

works perfect for all api levels except 21 (5.x),

if you have a manifest like above you get the following problem on installation:

INSTALL_FAILED_DUPLICATE_PERMISSION perm=com.google.android.c2dm.permission.RECEIVE pkg=com.google.android.gsf

Google nearly says nothing, possibly many people just dropping api level 10, but we have to still make it possible. So any solution already known?

cheers && thx