在JSP中获取嵌套形式的select列表值

My Main JSP调用displayProjectLayout.JSP文件，该文件显示下拉列表。我需要从下拉列表中获取选定的值，但由于jsp中的嵌套形式，我无法在mobilechangeProject操作中获取选择列表值。我需要保留这两张表格。

MY displayProjectLayout.jsp file: //common JSP
<script>
function submitProjectCode(){
    document.frm.action='/mobilechangeProject.action'; //calls action
    document.frm.submit();
}
</script>
<s:form  id="frm" theme="simple"> //2nd form
        <div class="shipAddress">
            <div class="shipbg">
                <label><s:text name="mobile.webshop.project.selection.label"/></label>
                <s:select list="{'Red', 'PO BOX 539', 'Green'}"
                onchange="javascript:submitProjectCode();" name="selectedProjectCode"  
                value="userContext.project.code" 
                cssStyle="width:100%; height:25px; padding: 0px!important; -webkit-appearance: menulist;" 
                theme="simple"/>
            </div>
            <s:if test="backURL != null" >
                <c:set var="url"><s:property value="backURL" /></c:set>
                <input type="hidden" name="currentUrl" value="${url}" />
            </s:if>
            <s:else>
                <input type="hidden" name="currentUrl" value="<%= request.getParameter("backAction")%>" />
            </s:else>
        </div>
        </s:form>
</s:if>
My Main JSP file: 
<s:form action="/mobileupdateBasket.action"  cssStyle="width:100%" id="basketFrm" name="basketFrm" theme="simple"> //1st form
//some other code
<c:if test="${empty param.displayProject || param.displayProject != false }">
                                                    <s:if test="isFileUsedForWebshop('/rexelmobile/xhtml/displayProjectLayout.jsp')">                                               
                                            </s:if> 

                                        </c:if>
</s:form>

//结束