function CheckInput()
		{
			var userAccount =(document.login_form.UserAccount.value);	
			if (userAccount=="")
			{
				alert("通行证用户名不能为空！");
   				document.login_form.UserAccount.focus();
				return false;	
			}
			if (userAccount.length<6 || userAccount.lenth>48)
			{
				alert("通行证用户名应该在6-48字节之间！");
   				document.login_form.UserAccount.focus();
				return false;	
			}
			var valid_char="abcdefghijklmnopqrstuvwxyz1234567890_-@.";
			var lowerChar=userAccount.toLowerCase();
			var i;
			for (i=0;i<=lowerChar.length;i++)
			{
    			var the_char=lowerChar.charAt(i);
				if(valid_char.indexOf(the_char)<0)
				{			
      				alert('通行证用户名不合法！')
      				document.login_form.UserAccount.focus();
      				return false;
    			}
			}
			var userPassword =(document.login_form.UserPassword.value);
			if(userPassword.length<6||userPassword.length>24)
			{
					alert("密码应该在6-24字节之间！");
					document.login_form.UserPassword.focus();
					return false;
			}
		    return  true; 	
		}

document.write("<table height='100%' border='0' cellpadding='0' cellspacing='0'><form name='login_form' id='login_form' method='post' action='http://reg.rising.com.cn/passport/commont/ikakalogin.aspx?url=http://forum.ikaka.com/index.asp?action=login' target='_self' onSubmit='JScript:if(CheckInput()==true){return true;}else{return false;}'>            <tr><td height='25' align='left' valign='middle'>通行证用户名</td></tr>            <tr><td align='left' valign='middle'><input name='UserAccount' type='input' size='16' maxlength='48'></td> </tr>            <tr>              <td height='25' align='left' valign='middle'>密&nbsp;&nbsp;码</td>            </tr>           <tr>              <td align='left' valign='middle'><input name='UserPassword' type='password' size='16' maxlength='24'>              </td>            </tr>            <tr>              <td height='25' align='left' valign='middle'><input type='submit' name='Submit' value=' 登 录 '>                <INPUT onclick=window.location='http://forum.ikaka.com/index.asp' type='button' value='浏览请进'><input type='hidden' name='CookieDate' id='CookieDate' value='1'></td>            </tr>           <tr>             <td height='25' align='left' valign='middle'><a href='http://reg.rising.com.cn/passport/www/reg_fast.aspx'>新用户注册</a> <a href='http://reg.rising.com.cn/passport/www/forgotpassword.aspx'>找回密码</a> <a href='http://forum.ikaka.com/help.asp'>帮助</a></td>            </tr>          </form></table>");