Example of overriding tags - not working as expected on Grails 2.2.1

Example.groovy

PluginATagLib {
  static namespace = "my"
  def input = { attrs, body ->
    out << attrs
  }
}

PluginBTagLib {
  static namespace = "my"
  static final String INPUT_CLASS = PluginATagLib.class.canonicalName
  def input = { attrs, body ->
    attrs.changeMe = "CHANGED"
    def tagLib = grailsApplication.mainContext.getBean(INPUT_CLASS)
    out << tagLib.input.call(attrs, body)
  }

}