Password not passed into DatabaseServerLoginModule

Trying to migrate an application to WildFly (from AS6.1) the migration went pretty smooth except for using the security domain.
The application uses a the ClientLoginModule on the client side and the DatabaseserverLoginModule on the server side.

Though the DatabaseServerLoginModule is called the validation of the password fails. I debugged it and the reason seems to be that in org.jboss.security.auth.callback.JBossCallbackHandler.getPassword() a org.jboss.as.security.remoting.RemotingConnectionCredential@22341334 is not handled and hence instead of a password the String org.jboss.as.security.remoting.RemotingConnectionCredential@22341334 is passed through to the DatabaseLoginModule.

See also DatabaseServerLoginModule broken? and the related posts