Well I am not sure about a4jCommandLink but i tried the same case with <h:commandLink> and found that it is working.
For your understanding I am providing the code too. Hope this will help you.
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The page Code
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<h:form>
<a4j:outputPanel id="banner" styleClass="banner" layout="block">
<a4j:outputPanel id="banlogo" styleClass="banlogo" layout="block">
<h:commandLink action="#{loginBean.login}" >
<h:graphicImage value="images/ui/logo1.gif"
width="180" height="60" style="border:none;">
</h:graphicImage>
</h:commandLink>
</a4j:outputPanel>
</a4j:outputPanel>
</h:form>
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The Bean Code
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public
String login() throws Exception {
System.err.println("in Login<------------------");
return "success";
}
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The Console Output
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[10/8/08 15:29:11:236 BST] 00000028 SystemErr R in Login<------------------
Himanshu
[ October 08, 2008: Message edited by: Himanshu Gupta ]