jstl - Type [java.lang.String] is not valid for option items upon migrating from Spring 3.0.6 to 3.2.3 -

i working on migrating dynamic web project spring 3.0.6 3.2.3. prior migration, had no issue our dropdowns. however, after migrating, following error:

exception created : com.ibm.websphere.servlet.error.servleterrorreport: javax.servlet.jsp.jspexception: type [java.lang.string] not valid option items 

i've removed code isolate issue, below relevant code. please let me know if further information needed. thing puzzles me list isn't string based. realize jsp treat values string options, understanding there built-in propertyeditor translation.

controller:

@requestmapping("/reports-menu.html") public string showreportshome(@modelattribute("reportform")reportform reportform, model model, httpsession session, httpservletresponse response, httpservletrequest request) {      list<integer> intlist = new arraylist<integer>();     intlist.add(1);     intlist.add(2);     intlist.add(3);      model.addattribute("intlist", intlist);       return "reports-home-int"; } 

jsp:

<%@ taglib uri="/web-inf/tld/c.tld" prefix="c" %> <%@ taglib uri="/web-inf/tld/fmt.tld" prefix="fmt" %> <%@ taglib uri="http://www.springframework.org/tags/form" prefix="form"%> <%@ taglib uri="http://www.springframework.org/tags" prefix="spring" %> <%@ taglib uri="/web-inf/tld/sbp.tld" prefix="sbp" %>  <form:form name="report_form" method="post" modelattribute="reportform" action="reports-menu.html" id="report_form"> <form:hidden path="download" id="form_download"/> <form:hidden path="sortdirection" /> <form:hidden path="sortby"/> <input type="hidden" name="reset"/> <div align="left"> <table border="0"> <tr> <td><b>mailer name</b></td> <td> <form:select path="mailercond"> <form:options items="${intlist}" /> </form:select> </td>                </tr> </table> </div> </form:form>