No I didn't have @DataModel before as I thought SelectOneMenu is just plain JSF and not Seam specific. But upon your hint I did put in @DataModel/@DataModelSelection as shown below. But I get the same problem. Nothing I do, short of removing the relevant xhtml snippet, make the ClassCastException go away! I am doing something grossly wrong. Thanks for your help | @DataModelSelection("allModelsSI") | public Model selectedModel; | public Model getSelectedModel(){return selectedModel;} | public void setSelectedModel(Model item){this.selectedModel = item;} | | @DataModel("allModelsSI") | private SelectItem[] allModelsSI; | public SelectItem[] getAllModelsSI(){return allModelsSI;} | public void setAllModelsSI(SelectItem[] allModelsSI){this.allModelsSI = allModelsSI;} | | View the original post : http://www.jboss.com/index.html?module=bb&op=viewtopic&p=3985758#... Reply to the post : http://www.jboss.com/index.html?module=bb&op=posting&mode=reply&a...