REQUEST.GETATRRIBUTE的错误

我得到一个LIST在STRUCTS 的ACITON当中，然后在ACTION中把这个REQUEST。SETATTRIBUTE（“SHIT”，LIST）结果得到如下错误：
69:  List it1 =(List) request.getAttribute("shit");
70: 
71:  if (it1 != null && page1 != null && totalPages != null) {
72:  Iterator it = it1.iterator();
Stacktrace:
org.apache.jasper.servlet.JspServletWrapper.handleJspException(JspServletWrapper.java:515)
org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:426)
org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:320)
org.apache.jasper.servlet.JspServlet.service(JspServlet.java:266)
javax.servlet.http.HttpServlet.service(HttpServlet.java:803)
org.apache.struts.action.RequestProcessor.doForward(RequestProcessor.java:1078)
org.apache.struts.action.RequestProcessor.processForwardConfig(RequestProcessor.java:396)
org.apache.struts.action.RequestProcessor.process(RequestProcessor.java:232)
org.apache.struts.action.ActionServlet.process(ActionServlet.java:1913)
org.apache.struts.action.ActionServlet.doGet(ActionServlet.java:449)
javax.servlet.http.HttpServlet.service(HttpServlet.java:690)
javax.servlet.http.HttpServlet.service(HttpServlet.java:803)
root cause java.lang.ClassCastException: java.util.AbstractList$Itr
org.apache.jsp.static_.store_jsp._jspService(store_jsp.java:158)
org.apache.jasper.runtime.HttpJspBase.service(HttpJspBase.java:70)
javax.servlet.http.HttpServlet.service(HttpServlet.java:803)
org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:384)
org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:320)
org.apache.jasper.servlet.JspServlet.service(JspServlet.java:266)
javax.servlet.http.HttpServlet.service(HttpServlet.java:803)
org.apache.struts.action.RequestProcessor.doForward(RequestProcessor.java:1078)
org.apache.struts.action.RequestProcessor.processForwardConfig(RequestProcessor.java:396)
org.apache.struts.action.RequestProcessor.process(RequestProcessor.java:232)
org.apache.struts.action.ActionServlet.process(ActionServlet.java:1913)
org.apache.struts.action.ActionServlet.doGet(ActionServlet.java:449)
javax.servlet.http.HttpServlet.service(HttpServlet.java:690)
javax.servlet.http.HttpServlet.service(HttpServlet.java:803)
说我第69报错，我真的不知道怎么去解决，希望各位大虾帮帮忙