<h:commandLink immediate="true"
        actionListener="#{localeChanger.changeLocale}">
        <f:attribute name="languageCode" value="de"/>
        <h:graphicImage value="/german_flag.gif" style="border: 0px"/>
     </h:commandLink>
     ...
     <h:commandLink immediate="true"
         actionListener="#{localeChanger.changeLocale}">
         <f:attribute name="languageCode" value="en"/>
         <h:graphicImage value="/british_flag.gif" style="border: 0px"/>
     </h:commandLink>