Struts validator框架问题，请高手指点！！！

我的validation.xml

<form-validation>
<global>
<constant>
<constant-name>txtUID</constant-name>
<constant-value>^\d{8}\d*$</constant-value>
</constant>

</global>
<formset>
<form name="loginForm">
<field property="txtUID" depends="required">
<msg key="required" name="errors.required"></msg>
<arg0 key="prompt.username" />
<!--arg1 name="minlength" key="${var:minlength}" resource="false" />

<var>
<var-name>minlength</var-name>
<var-value>10</var-value>
</var-->
</field>
<field property="txtPwd" depends="required">
<arg0 key="prompt.password" />
</field>
</form>
</formset>
</form-validation>


我的jsp

<td width="104">用户帐号：</td>
<td width="270"><input name="txtUID" type="text" value="<c:out value="${uid}"/>" readonly="true"/><html:errors property="txtUID"/></td>
</tr>
<tr>
<td>用户密码：</td>
<td><input type="text" name="txtPwd"/><html:errors property="txtPwd"/></td>
</tr>

我的struts-config.xml

<form-beans >
<form-bean name="regForm" type="org.apache.struts.validator.DynaValidatorForm">
<form-property name="txtUID" type="java.lang.Long"/>
<form-property name="txtPwd" type="java.lang.String"/>
</form-bean>
</form-beans >


<global-forwards>
<forward name="login" path="/lg"/>
</global-forwards>
<action-mappings >
<action
name="regForm"
input="/WEB-INF/jsp/register.jsp"
scope="request"
path="/rg"
parameter="m"
validate="true"
type="com.hongmedio.struts.action.RegisterAction">
<forward name="rg1" path="/WEB-INF/jsp/register.jsp"/>
<forward name="success" path="/WEB-INF/jsp/loginSuccess.jsp"/>
</action>

</action-mappings >

<message-resources parameter="com.hongmedio.struts.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>


我的action文件

ServletContext myContext = getServlet().getServletContext();
ApplicationContext ap = WebApplicationContextUtils.getWebApplicationContext(myContext);
ProfileService ps=(ProfileService)ap.getBean("Adv.profile");
DynaValidatorForm rf=(DynaValidatorForm)form;
long uid=(Long)rf.get("txtUID");
String pwd=(String)rf.get("txtPwd");
System.out.println(uid+" -------------------------------- "+pwd);

request.setAttribute("adm", 1);
return mapping.findForward("success");

为什么不显示错误信息？？？