跨域名提交登录

当前网站www.a.com的页面a.jsp：
在画面上增加登录到www.b.com的功能：
form,table,提交时，from的action为带域名www.b.com的.do形式的url，from.submit后就可以实现在www.a.com网站上登录到www.b.com的后台

<form action="http://www.b.com/Login.do?method=login" method="post" id="jxForm">
        <table width="213" border="0" cellspacing="0" cellpadding="0" class="qyLogin">
          <tr>
            <td width="66" height="35" align="right" valign="middle" class="font1">用　户：</td>
            <td colspan="2"><input name="user_name" id="username" type="text" value="" style="width: 142px" class="input02"/></td>
          </tr>
          <tr>
            <td height="36" align="right" valign="middle" class="font1">密　码：</td>
            <td colspan="2"><input name="pass_word" id="password" type="password" value="" style="width: 142px" class="input02"/></td>
          </tr>
          <tr>
            <td height="31" align="right" valign="middle" class="font1">验证码：</td>
            <td width="78" align="left" valign="middle"><input name="verificationCode"  id="verificationCode" type="text" value=""  maxlength="4" size="10" class="input02"/></td>
            <td width="69" align="left" valign="middle">&nbsp;<img src=""http://www.b.com/styles/images/VerificationCode.jpg" id="verpic" style="vertical-align:middle;border:1px solid #A1BCA3;cursor:pointer;" onclick="this.src = this.src + '?t=' + new Date().getTime();" /></td>
          </tr>
          <tr>
            <td height="33">&nbsp;</td>
            <td valign="bottom"><input type="image" src="${ctx}/styles/indexv3/images/pic23.jpg"  /></td>
            <td valign="bottom"><a href="javascript:resetForm(2)"><img src="${ctx}/styles/indexv3/images/pic44.jpg"  /></a></td>
          </tr>
        </table>
      </form>