Problem with Struts Validator

[kevarouza]

Can't seem to get the Struts Validator to load. I'm getting the
following error at Startup. Using Struts 1.2 and Tomcat 3.2.

[ERROR] Digester - Parse Error at line 56 column 68: Element type
"plug-in" must be declared. <org.xml.sax.SAXParseException: Element
type "plug-in" must be declared.>org.xml.sax.SAXParseException: Element
type "plug-in" must be declared.

my struts-config.xml file looks like this:

<!DOCTYPE struts-config PUBLIC
"-//Apache Software Foundation//DTD Struts Configuration 1.0//EN"
"http://jakarta.apache.org/struts/dtds/struts-config_1_2.dtd">

<struts-config>
....other stuff...

<plug-in className="org.apache.struts.validator.ValidatorPlugIn">
<set-property property="pathnames"
value="/WEB-INF/validator-rules.xml, /WEB-INF/validation.xml"/>
</plug-in>

</struts-config>

I looked at the referenced DTD and it does define the "plug-in" element
but for some reason the parser is not validating the XML against the
specified DTD but rather something else. Any ideas on what could be
wrong?

Thanks,
Kevin