javax.naming.AuthenticationException:[LDAP:错误代码49-无效凭据]在spring security3中通过LDAP进行身份验证时

我正在尝试通过LDAP对用户进行身份验证，并通过数据库进行授权。LDAP目录包含具有相应组的用户，我希望在成功身份验证时获取此组，并在身份验证后从数据库中获取具有相应组的角色

下面是我的spring安全配置文件

<beans xmlns="http://www.springframework.org/schema/beans"
    xmlns:security="http://www.springframework.org/schema/security"
    xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
    xsi:schemaLocation="http://www.springframework.org/schema/beans 
              http://www.springframework.org/schema/beans/spring-beans-3.1.xsd
              http://www.springframework.org/schema/security 
              http://www.springframework.org/schema/security/spring-security-3.1.xsd">


    <bean id="authenticationEntryPoint"
        class="org.springframework.security.web.authentication.LoginUrlAuthenticationEntryPoint">
        <property name="loginFormUrl" value="/login.htm" />
    </bean>

    <bean class="org.springframework.security.web.access.expression.DefaultWebSecurityExpressionHandler" />

    <security:http security="none" pattern="/login.htm"/>
    <security:http security="none" pattern="/js/**"/>
    <security:http security="none" pattern="/images/**"/>
    <security:http security="none" pattern="/css/**"/>
    <security:http security="none" pattern="/ckeditor/**"/>
    <security:http security="none" pattern="/dhtmlgrid/**"/>
    <security:http security="none" pattern="/xmleditor/**"/>


    <security:http auto-config="false" entry-point-ref="authenticationEntryPoint" disable-url-rewriting="true" use-expressions="true">

        <security:session-management>
            <security:concurrency-control error-if-maximum-exceeded="true" max-sessions="1"/>
        </security:session-management>

        <security:custom-filter position="FORM_LOGIN_FILTER"
            ref="cdlAuthenticationProcessingFilter" />

        <security:intercept-url pattern="/displayAdminPage.htm" access="hasRole('admin')" />
        <security:intercept-url pattern="/**" access="isFullyAuthenticated()" />
        <security:access-denied-handler ref="accessDeniedHandler" />
        <security:logout logout-success-url="/login.htm" logout-url="/logout"/>
    </security:http>

    <security:authentication-manager alias="authenticationManager">

       <security:authentication-provider ref="customLdapAuthenticationProvider"/>

       <security:authentication-provider user-service-ref="cdlUserDetailService">
       </security:authentication-provider>
    </security:authentication-manager>

    <bean id="customLdapAuthenticationProvider" class="com.qait.cdl.authentication.customfilter.CustomLdapAuthenticationProvider">
       <constructor-arg ref="ldapBindAuthenticator"/>
       <constructor-arg ref="ldapAuthoritiesPopulator"/>
    </bean>

    <bean id="ldapBindAuthenticator"
          class="org.springframework.security.ldap.authentication.BindAuthenticator">
        <constructor-arg ref="ldapContextSource" />
        <property name="userDnPatterns"><list><value>uid={0},cn=users</value></list></property>
    </bean>

     <bean id="ldapAuthoritiesPopulator" class="com.qait.cdl.authentication.customfilter.CdlUserAuthoritiesPopulator">
     </bean>

    <bean id="ldapContextSource"
       class="org.springframework.security.ldap.DefaultSpringSecurityContextSource">
     <constructor-arg value="ldap://172.16.1.121:389/dc=nodomain"/>
     <property name="userDn" value="cn=users,dc=nodomain"/>
     <property name="password" value="ldap_admin"/>
   </bean>

    <bean id="cdlUserDetailService" class="com.qait.cdl.authentication.service.impl.UserDetailsServiceImpl">
        <property name="userDao" ref="userDao"/>
    </bean>

    <bean id="cdlAuthenticationProcessingFilter"
        class="com.qait.cdl.authentication.customfilter.CustomAuthenticationProcessingFilter">
        <property name="authenticationManager" ref="authenticationManager" />
        <property name="userDao" ref="userDao"/>
    </bean>

    <bean id="accessDeniedHandler"
        class="org.springframework.security.web.access.AccessDeniedHandlerImpl">
       <property name="errorPage" value="/WEB-INF/jsp/access-denied/content.jsp"/>
    </bean>

</beans>     

在过去的两天里，我一直在努力解决这个错误。如果您需要任何帮助，我们将不胜感激。如果您需要任何额外的信息，请告诉我。可能是，我的LDAP目录结构错误。我哪里错了，我不知道

My LDAP directory structure is below:

dn: uid=user1,cn=users,dc=nodomain  
uid: user1
userPassword:user1