Strange behaviour with h:selectOneMenu value

[Amr Khaled]

I am having a page with two selectOneMenu, The 2nd one is rendered when the 2nd select item of the 1st selectOneMenu is selected until now it is Ok,
The problem that value submitted from the 2nd selectOneMenu is not correct and sometimes null

	<f:view>
		<h:form>		
			<rich:simpleTogglePanel switchType="client"
				label="Test">
				<h:outputLabel>Choose a Category 1:</h:outputLabel>
				<h:selectOneMenu styleClass="out" value="#{reportsPage.firstComboValue}" > 
					<f:selectItems value="#{reportsPage.firstComboSelectItems}" />
					<a4j:support event="onchange" reRender="setupControls"
						action="#{reportsPage.setupControls}"  />
				</h:selectOneMenu>
				<h:panelGrid columns="2">
					<a4j:outputPanel id="setupControls" layout="block">					
						<h:outputLabel>Choose a Category 2:</h:outputLabel>
						<h:selectOneMenu styleClass="out" 
							rendered="#{reportsPage.secondComboRendered}" 
							value="#{reportsPage.secondComboValue}">
							<f:selectItems value="#{reportsPage.secondComboSelectItems}" />
						</h:selectOneMenu>
					</a4j:outputPanel>
				</h:panelGrid>
				<h:commandButton immediate="true" value="Submit"
					action="#{reportsPage.submit}" />
			</rich:simpleTogglePanel>
		</h:form>
	</f:view>

public class ReportsPage {
	
	private String firstComboValue;
	
	private String secondComboRendered = "false";
	private String secondComboValue;
	
	private static SelectItem[] firstComboSelectItems	= new SelectItem[]{
			new SelectItem("1", "Select1"),
			new SelectItem("2", "Select2"),
			new SelectItem("3", "Select3")
	};	
	

	public ReportsPage() {
		
	}
	
	public String setupControls() {
		if (firstComboValue.equals("2")) {
			secondComboRendered = "true";
		}
		else 
			secondComboRendered = "false";
		return null;
	}
	
	public String submit(){
		System.out.println("First Combo value: " + firstComboValue);
		System.out.println("Second Combo value: " + secondComboValue);
		return null;
	}
	
	public javax.faces.model.SelectItem[] getSecondComboSelectItems()  {
		SelectItem[] select = new SelectItem[] {
				new SelectItem("10", "Select2.1"),
				new SelectItem("11", "Select2.2")
		};  		
		
		return select;  		
	}

	public String getFirstComboValue() {
		return firstComboValue;
	}

	public void setFirstComboValue(String firstComboValue) {
		this.firstComboValue = firstComboValue;
	}

	public String getSecondComboRendered() {
		return secondComboRendered;
	}

	public void setSecondComboRendered(String secondComboRendered) {
		this.secondComboRendered = secondComboRendered;
	}
	
	
	public SelectItem[] getFirstComboSelectItems() {
		return firstComboSelectItems;
	}

	public void setSecondComboValue(String secondComboValue) {
		this.secondComboValue = secondComboValue;
	}
	
	public String getSecondComboValue(){
		return secondComboValue;
	}
	
}