我用struts2写了一个小程序 ， 我导入struts2-core-2.1.6程序就能完美运行

可是如果我把struts2-core-2.1.6替换成struts2-core-2.2.1.1 就不行了 还报错是 The server encountered an internal error () that prevented it from fulfilling this request. The server encountered an internal error () that prevented it from fulfilling this request.java.lang.NoClassDefFoundError: org/apache/commons/lang/xwork/ObjectUtils请问如何修正！！！！！！！description The server encountered an internal error () that prevented it from fulfilling this request.exception javax.servlet.ServletException: Filter execution threw an exceptionroot cause java.lang.NoClassDefFoundError: org⼀apache⼀commons⼀lang⼀xwork⼀ObjectUtils