f:ajax listener never fired

i'm using JSF 2.0 primefaces 2.2 a开发者_运维技巧nd Spring 3.0.5. I have a little problem usign f:ajax listener that wasn't fired. This is the code:

<h:form prependId="false" >
   <h:selectOneRadio value="#{autoBean.newAuto.marca}">
        <f:selectItem itemValue="aa"/>
        <f:selectItem itemValue="bb"/>
        <f:ajax event="click" listener="#{autoBean.update}" />
    </h:selectOneRadio>
</h:form>

and this is the method:

public void update(AjaxBehaviorEvent event)
{
}

any idea? Thank you in advance

UPDATE Sorry, but the problem isn't simply to explain...

I guess you've missed to specify which event you want to trigger the ajax update:

<f:ajax event="keyup" ... />