I thought the MapCompositeMetaType contained a map of potential keys, for the purpose of enumerating the allowed keys and optionally specifying descriptions for those keys. If that is true, it should not be desirable to remove the corresponding item from the metatype when an item is removed from a MapCompositeValueSupport, and it should not be necessary to add a keyset() method to MapCompositeValueSupport. However, if MapCompositeMetaType doesn't enumerate all allowed keys, but just ones that have descriptions, then keySet() would need to be added, since the MapCompositeValueSupport could contain additional items that are not enumerated in the metatype. View the original post : http://www.jboss.org/index.html?module=bb&op=viewtopic&p=4226249#... Reply to the post : http://www.jboss.org/index.html?module=bb&op=posting&mode=reply&a...