rich:modalPanel display problem

[Dreambig]

I have got a rich modal panel that gets displayed once the user hits the save button. However, if the form validation fails, the modal panel should not be displayed. Within the save button action method savePromotion(), I set a boolean displayModalPanel property to false if validation fails and to true if if it succeeds (by default it's set to true). Then using rich:componentControl, I display the modal panel which should be rendered only if the displayModalPanel is true. I use the rendered attribute of componentControl to control that. The problem: the modal panel always displays even if the displayModalPanel set to false within savePromotion() method. It seems somehow the rendered is not being re-evaluated. I am not sure how I can get this to work. Any help will be greatly appreciated.


<a4j:commandButton value="save"
action="#{AddPromotion.savePromotion}">
<rich:componentControl for="savePromoPanel"
operation="show"
event="oncomplete"
rendered="#{AddPromotion.displayModalPanel}"/>
</a4j:commandButton>


<rich:modalPanel id="savePromoPanel" width="350" height="150">
<!-- modal panel code here -->
</rich:modalPanel>

//Java code
boolean displayModalPanel = true;

public boolean isdisplayModalPanel () {
return displayModalPanel ;
}

public void setdisplayModalPanel (boolean displayModalPanel ) {
this.displayModalPanel = displayModalPanel ;
}



public void savePromotion () {
// other code here

if (validationFailed)
setdisplayModalPanel (false);
else
setdisplayModalPanel (true);
}