rich:tree control problem

[ramanujareddy]

hi every one,i have a problem on rich:tree control i.e, i am unable to open seleted node after page refreshing.
here is my code.

<rich:tree id="treenode" adviseNodeSelected="#{canalNetwork.openNode()}" 
                                        value="#{canalNetwork.data}" var="node" selectedClass="nodeSel" adviseNodeOpened="#{canalNetwork.openNode()}"
                                        switchType="client" style="width:280px;" preserveModel="state">
                                            
                                            <rich:treeNode ajaxSingle="true" 
                                            iconLeaf="img/singer.gif" icon="img/singer.gif" selectedClass="nodeSel">
                                                
                                                <s:link action="#{canalNetwork.selectCanal}">
                                                    <f:param name="tnode" value="#{node}" />
                                                    
                                                    <h:outputText  value="#{node}" />
                                                    
                                                </s:link>
                                                
                                            </rich:treeNode>
                                            
                                        </rich:tree>