struts+spring+sitemesh下的中文乱码问题

最近有个项目用struts+spring+sitemesh做的框架，struts用的是1.2版本的。spring用的是2.0的。sitemesh是2.3版本。发现每次在jsp页面中进行更新操作时，在数据库中总是更新成了乱码。
网上搜了一下，发现问题在这里，这是我的正确的web.xml配置：

<?xml version="1.0" encoding="UTF-8"?>
<web-app xmlns="http://java.sun.com/xml/ns/j2ee" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" version="2.4" xsi:schemaLocation="http://java.sun.com/xml/ns/j2ee   http://java.sun.com/xml/ns/j2ee/web-app_2_4.xsd">
  <context-param>
    <param-name>contextConfigLocation</param-name>
    <param-value>/WEB-INF/ds-definition.xml /WEB-INF/dao-definition.xml
			/WEB-INF/applicationContext.xml /WEB-INF/struts-spring.xml</param-value>
  </context-param>
  <filter>
    <filter-name>sitemesh</filter-name>
    <filter-class>com.opensymphony.module.sitemesh.filter.PageFilter</filter-class>
    <init-param>
      <param-name>debug.pagewriter</param-name>
      <param-value>true</param-value>
    </init-param>
  </filter>
  <filter> 
  <filter-name>encodingFilter</filter-name>
  <filter-class>org.springframework.web.filter.CharacterEncodingFilter</filter-class>
  <init-param>
   <param-name>encoding</param-name> 
   <param-value>GBK</param-value>
  </init-param>
  <init-param>
   <param-name>forceEncoding</param-name>
   <param-value>true</param-value>
  </init-param> 
 </filter>
  
  <filter-mapping>
   <filter-name>encodingFilter</filter-name>
    <url-pattern>/*</url-pattern>
  </filter-mapping>
  <filter-mapping>
    <filter-name>sitemesh</filter-name>
    <url-pattern>/*</url-pattern>
  </filter-mapping>
  <listener>
    <listener-class>org.springframework.web.context.ContextLoaderListener</listener-class>
  </listener>
  <servlet>
    <servlet-name>taxs_Admin</servlet-name>
    <servlet-class>org.apache.struts.action.ActionServlet</servlet-class>
    <init-param>
      <param-name>config</param-name>
      <param-value>/WEB-INF/struts-config.xml</param-value>
    </init-param>
    <init-param>
      <param-name>debug</param-name>
      <param-value>3</param-value>
    </init-param>
    <init-param>
      <param-name>detail</param-name>
      <param-value>3</param-value>
    </init-param>
    <load-on-startup>0</load-on-startup>
  </servlet>
  <servlet>
    <servlet-name>action</servlet-name>
    <servlet-class>org.apache.struts.action.ActionServlet</servlet-class>
    <init-param>
      <param-name>config</param-name>
      <param-value>/WEB-INF/struts-config.xml</param-value>
    </init-param>
    <init-param>
      <param-name>debug</param-name>
      <param-value>3</param-value>
    </init-param>
    <init-param>
      <param-name>detail</param-name>
      <param-value>3</param-value>
    </init-param>
    <load-on-startup>0</load-on-startup>
  </servlet>
  <servlet-mapping>
    <servlet-name>taxs_Admin</servlet-name>
    <url-pattern>*.do</url-pattern>
  </servlet-mapping>
  <error-page>
    <error-code>404</error-code>
    <location>/error.jsp</location>
  </error-page>
  <welcome-file-list>
    <welcome-file>index.jsp</welcome-file>
  </welcome-file-list>
  <jsp-config>
    <taglib>
      <taglib-uri>/WEB-INF/tld/struts/struts-bean.tld</taglib-uri>
      <taglib-location>/WEB-INF/tld/struts/struts-bean.tld</taglib-location>
    </taglib>
    <taglib>
      <taglib-uri>/WEB-INF/tld/struts/struts-html.tld</taglib-uri>
      <taglib-location>/WEB-INF/tld/struts/struts-html.tld</taglib-location>
    </taglib>
    <taglib>
      <taglib-uri>/WEB-INF/tld/struts/struts-logic.tld</taglib-uri>
      <taglib-location>/WEB-INF/tld/struts/struts-logic.tld</taglib-location>
    </taglib>
    <taglib>
      <taglib-uri>/WEB-INF/tld/struts/struts-nested.tld</taglib-uri>
      <taglib-location>/WEB-INF/tld/struts/struts-nested.tld</taglib-location>
    </taglib>
    <taglib>
      <taglib-uri>/WEB-INF/tld/struts/struts-tiles.tld</taglib-uri>
      <taglib-location>/WEB-INF/tld/struts/struts-tiles.tld</taglib-location>
    </taglib>
    <taglib>
      <taglib-uri>/WEB-INF/tld/sitemesh/sitemesh-decorator.tld</taglib-uri>
      <taglib-location>/WEB-INF/tld/sitemesh/sitemesh-decorator.tld</taglib-location>
    </taglib>
    <taglib>
      <taglib-uri>/WEB-INF/tld/sitemesh/sitemesh-page.tld</taglib-uri>
      <taglib-location>/WEB-INF/tld/sitemesh/sitemesh-page.tld</taglib-location>
    </taglib>
    <taglib>
      <taglib-uri>/WEB-INF/tld/framework/framework-html.tld</taglib-uri>
      <taglib-location>/WEB-INF/tld/framework/framework-html.tld</taglib-location>
    </taglib>
    <taglib>
      <taglib-uri>/WEB-INF/tld/framework/framework-role.tld</taglib-uri>
      <taglib-location>/WEB-INF/tld/framework/framework-role.tld</taglib-location>
    </taglib>
    <taglib>
      <taglib-uri>/WEB-INF/tld/jstl/c.tld</taglib-uri>
      <taglib-location>/WEB-INF/tld/jstl/c-1_0.tld</taglib-location>
    </taglib>
    <taglib>
      <taglib-uri>/WEB-INF/tld/jstl/x.tld</taglib-uri>
      <taglib-location>/WEB-INF/tld/jstl/x-1_0.tld</taglib-location>
    </taglib>
  </jsp-config>
</web-app>