function show_message(content, message, width, height) {
    if(document.getElementById('message_div')) {
        document.body.removeChild(document.getElementById('message_div'));
    }
    var message_div = document.getElementById('message_div');
    var topPosition = parseInt( posTop() + parseInt((document.viewport.getHeight()- height)/2)-20);
    if ( !message_div ) {
    message_div = document.createElement('div');
    message_div.align='center';
    message_div.id = 'message_div';
    message_div.style.width = width + 'px';
    message_div.style.height = height + 'px';
    message_div.style.left =  (parseInt((document.viewport.getWidth()- width)/2)-20) + 'px';
    message_div.style.top = topPosition + 'px';
    document.body.appendChild( message_div );
    message_div.innerHTML = '<table onclick="close_message();" width="100%" border="0" cellpadding="0" cellspacing="0"><tr><td width="148" align="left" valign="top" style="text-align:left;" height="'+height+'"><img src="/images/site/alert.png" alt="' + message + '"></td><td valign="top"><img src="/images/site/cancel.png" alt="" style="cursor:pointer;float:right;" onclick="close_message();" /><div align="left"><h1>'+message+'</h1><span>' + content + '</span></div></td></tr></table>';
}
    message_div.style.display='block';
    return false;
}

function close_message() {
    el = document.getElementById('message_div');
    // Obtenemos el padre de dicho elemento
    // con la propiedad “parentNode”
    var padre = el.parentNode;
    // Eliminamos el hijo (el) del elemento padre
    padre.removeChild(el);
}

// Browser Window Size and Position
// copyright Stephen Chapman, 3rd Jan 2005, 8th Dec 2005
// you may copy these functions but please keep the copyright notice as well
function pageWidth() {return window.innerWidth != null? window.innerWidth : document.documentElement && document.documentElement.clientWidth ?       document.documentElement.clientWidth : document.body != null ? document.body.clientWidth : null;} function pageHeight() {return  window.innerHeight != null? window.innerHeight : document.documentElement && document.documentElement.clientHeight ?  document.documentElement.clientHeight : document.body != null? document.body.clientHeight : null;} function posLeft() {return typeof window.pageXOffset != 'undefined' ? window.pageXOffset :document.documentElement && document.documentElement.scrollLeft ? document.documentElement.scrollLeft : document.body.scrollLeft ? document.body.scrollLeft : 0;} function posTop() {return typeof window.pageYOffset != 'undefined' ?  window.pageYOffset : document.documentElement && document.documentElement.scrollTop ? document.documentElement.scrollTop : document.body.scrollTop ? document.body.scrollTop : 0;} function posRight() {return posLeft()+pageWidth();} function posBottom() {return posTop()+pageHeight();}