validação em struts

Ola pessoal…

É o seguinte:

Estou tentando validar campo usuario e senha na aplicacao em struts, e quero fazer isto com validator. O campo de usuario e senha devem ser obrigatorios. Na minha aplicacao, quando eu submeto a pagina com os campos vazios, ela abre a pagina que inicia a aplicação e não a pagina de login mostrando os erros como deveria de ser.

struts-config.xml:

<struts-config>
	<form-beans>
		<form-bean name="loginForm" type="org.apache.struts.validator.DynaValidatorForm">		 		
			<form-property name="username" type="java.lang.String"/>
			<form-property name="password" type="java.lang.String"/>
		</form-bean>
	</form-beans>
	<action-mappings>
		<action path="/login"
				type="br.com.teclogica.toystore.controller.LoginAction"
				name="loginForm"
				input="login.jsp"				
				validate="true">
			<forward name="index" path="index.jsp"/>
			<forward name="login" path="login.jsp"/>	
		</action>				
	</action-mappings>	
	
	<message-resources parameter="br.com.teclogica.toystore.ApplicationResources"/>
	
	<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>

validation.xml:

<form name="loginForm">
			<field property="username" depends="required">
				<arg0 key="username" />
			</field>
			<field property="password" depends="required">
				<arg0 key="password" />				
			</field>			
		</form>

login.jsp:

<%@taglib uri="struts-html" prefix="html"%>
<%@taglib uri="struts-form" prefix="form"%>
<%@taglib uri="struts-bean" prefix="bean"%>
<%@taglib uri="struts-logic" prefix="logic" %>

<html>
<head>
<title>Sign In</title>
</head>
<body>

<br>
<br>
<center>
	<html:form action="login.do">    
        <input type="hidden" name="dscAcao" value="login">
        <table>
        
        <%-- include do bloco de mensagens --%>
		<%@ include file="mensagens.jspf" %>
		
            <tr>
                <td align="center" ><table border="0">
                        <tr>
                            <td align="right"><b><label><bean:message key="label.login.username"/><label/></b></td>
                            <td> <html:text property="username"/>
                            </td>
                            <td></td>
                        </tr>
                        <tr>
                            <td align="right"><b><label><bean:message key="label.login.password"/><label/></b></td>
                            <td> <html:password property="password"/>
                            </td>
                            <td></td>
                        </tr>
                        <tr>
                            <td></td>
                            <td align="left">
                            <html:image src="images/button_sign-in.gif" property="submit" onclick="this.form.submit();" border="0"/>                            
                            </td>
                            <td></td>
                        </tr>                                                
                    </table></td>
            </tr>
        </table>
    </html:form>
</center>
</body>
</html>