jumperchen/zk — pull request #20 by MontyPan (2012-05-24 04:37:08+00:00)
Title: B60-ZK-1147: The returning type of getModel API in combobox and tree component shall be the same 

http://tracker.zkoss.org/browse/ZK-1147
also fix the same problem in org.zkoss.zul.Radiogroup