function CheckLoginForm()    
    {    
        if (!CheckField('UserName', /.{4,16}/))
        {
            return false;
        }    
        if (!CheckField('Password', /.{4,16}/))
        {
            return false;
        } 
        
        getObject('md5').value = hex_hmac_md5(getObject('key').value, hex_md5(getObject('Password').value)); 
        getObject('Password').value = '';
        
        return true; 
    }