org.springframework.security.authentication.BadCredentialsException: Bad credentials

org.springframework.security.authentication.BadCredentialsException: Bad credentials
	at org.springframework.security.authentication.dao.DaoAuthenticationProvider.additionalAuthenticationChecks(DaoAuthenticationProvider.java:87)
	at org.springframework.security.authentication.dao.AbstractUserDetailsAuthenticationProvider.authenticate(AbstractUserDetailsAuthenticationProvider.java:149)
	at org.springframework.security.authentication.ProviderManager.authenticate(ProviderManager.java:156)

修改前

<beans:bean id="daoAuthenticationProvider" class="org.springframework.security.authentication.dao.DaoAuthenticationProvider">  
   	<beans:property name="userDetailsService" ref="userDetailService" />  
</beans:bean>

修改后

<beans:bean id="daoAuthenticationProvider" class="org.springframework.security.authentication.dao.DaoAuthenticationProvider">  
   	<beans:property name="userDetailsService" ref="userDetailService" />  
   	<beans:property name="passwordEncoder" ref="md5PasswordEncoder" />  
</beans:bean>
<beans:bean id="md5PasswordEncoder" class="org.springframework.security.authentication.encoding.Md5PasswordEncoder" />