As you can see on [1], there is a validation invoked, but with wrong parameter. It's trying to validate currently persisted application (the one in database) which has to be correct, but it should try to verify the "updatedPushApp" which is the one from user.

1 - https://github.com/aerogear/aerogear-unifiedpush-server/blob/master/jaxrs/src/main/java/org/jboss/aerogear/unifiedpush/rest/registry/applications/PushApplicationEndpoint.java#L118