function Grise(login,tracker) {
        var objBody = document.getElementsByTagName("body").item(0);

        var arrayPageSize = getPageSize();
        var arrayPageScroll = getPageScroll();
        // create overlay div and hardcode some functional styles (aesthetic styles are in CSS file)
        var objOverlay = document.createElement("div");
        objOverlay.setAttribute('id','overlay');
        objOverlay.onclick = function () {hideLightbox(); return false;}
        objOverlay.style.position = 'absolute';
        objOverlay.style.top = '0';
        objOverlay.style.left = '0';
        objOverlay.style.zIndex = '90';
        objOverlay.style.width = '100%';
	objOverlay.style.height = (arrayPageSize[1] + 'px');
        objBody.insertBefore(objOverlay, objBody.firstChild);
        objOverlay.style.display = 'block';



        // create lightbox div, same note about styles as above
        var objLightbox = document.createElement("div");
        objLightbox.setAttribute('id','formlightbox');
	objLightbox.innerHTML = '<IFRAME NAME="AccesCharmiX" WIDTH=366 HEIGHT=378 TOPMARGIN=0 MARGINWIDTH=0 MARGINHEIGHT=0 HSPACE=0 VSPACE=0 FRAMEBORDER=0 SCROLLING=NO ALLOWTRANSPARENCY=TRUE SRC="http://www.cyberflirt.fr/form.php?login=' + login + '&tracker=' + tracker + '"></IFRAME>';
        objLightbox.style.position = 'absolute';
        objLightbox.style.zIndex = '100';
	objLightbox.style.top = (arrayPageScroll[1] + ((arrayPageSize[3] - 35 - 378) / 2) + 'px');
	objLightbox.style.left = (((arrayPageSize[0] - 20 - 366) / 2) + 'px');
        objBody.insertBefore(objLightbox, objOverlay.nextSibling);
	objBody.style.display = 'block';
}


function hideLightbox()
{
        // get objects
        objOverlay = document.getElementById('overlay');
        objLightbox = document.getElementById('formlightbox');

        // hide lightbox and overlay
        objOverlay.style.display = 'none';
        objLightbox.style.display = 'none';

        // make select boxes visible
        selects = document.getElementsByTagName("select");
	for (i = 0; i != selects.length; i++) {
                selects[i].style.visibility = "visible";
        }

        // disable keypress listener
        document.onkeypress = '';
}

function getPageScroll(){

        var yScroll;

        if (self.pageYOffset) {
                yScroll = self.pageYOffset;
        } else if (document.documentElement && document.documentElement.scrollTop){      // Explorer 6 Strict
                yScroll = document.documentElement.scrollTop;
        } else if (document.body) {// all other Explorers
                yScroll = document.body.scrollTop;
        }

        arrayPageScroll = new Array('',yScroll)
        return arrayPageScroll;
}

function getPageSize(){

        var xScroll, yScroll;

        if (window.innerHeight && window.scrollMaxY) {
                xScroll = document.body.scrollWidth;
                yScroll = window.innerHeight + window.scrollMaxY;
        } else if (document.body.scrollHeight > document.body.offsetHeight){ // all but Explorer Mac
                xScroll = document.body.scrollWidth;
                yScroll = document.body.scrollHeight;
        } else { // Explorer Mac...would also work in Explorer 6 Strict, Mozilla and Safari
                xScroll = document.body.offsetWidth;
                yScroll = document.body.offsetHeight;
        }

        var windowWidth, windowHeight;
        if (self.innerHeight) { // all except Explorer
                windowWidth = self.innerWidth;
                windowHeight = self.innerHeight;
        } else if (document.documentElement && document.documentElement.clientHeight) { // Explorer 6 Strict Mode
                windowWidth = document.documentElement.clientWidth;
                windowHeight = document.documentElement.clientHeight;
        } else if (document.body) { // other Explorers
                windowWidth = document.body.clientWidth;
                windowHeight = document.body.clientHeight;
        }

        // for small pages with total height less then height of the viewport
        if(yScroll < windowHeight){
                pageHeight = windowHeight;
        } else {
                pageHeight = yScroll;
        }

        // for small pages with total width less then width of the viewport
        if(xScroll < windowWidth){
                pageWidth = windowWidth;
        } else {
                pageWidth = xScroll;
        }


        arrayPageSize = new Array(pageWidth,pageHeight,windowWidth,windowHeight)
        return arrayPageSize;
}