503 error: Servlet action is currently unavailable

I have developed a Struts app where the user orders something and is then sent a confirmation email.

I have had no issues (save for minor errors) up until now.

My application now throws this error:

Sep 22, 2006 4:19:31 PM org.apache.catalina.core.StandardWrapperValve invoke
INFO: Servlet action is currently unavailable

This only occurs after I have added this action to struts config:

<action path="/ConfirmOrderEmail"
type="com.mullen.cac.struts.action.OrderConfirmEmailAction"
scope="request">
<forward name="success" path="/EmailConfirmSuccess.do" redirect="true" />
<forward name="failure" path="/EmailConfirmFailure.do" redirect="true" />
</action>

What could be causing this, I see now error in my xml.

One possible reason for this error would be if the Action class com.mullen.cac.struts.action.OrderConfirmEmailAction doesn't exist. Check for spelling errors. Also, make sure you haven't overridden the default no-args constructor of the Action class or made the constructor non-public.