function shownewsLetterPop(categories){
          var scrolltop = $(window).scrollTop();
            var pageHeight= $(window).height();
            var pageWidth = $(window).width();
            var bodyheight = ($('body').outerHeight());
            
            $('#key_overlay').remove();
            $('#key_iframe').remove();
            var overLayDiv = document.createElement('div');
            $(overLayDiv).attr('style','position:absolute;top:0;left:0;width:100%;height:'+(bodyheight)+'px;z-index:1000;display:none;position:absolute;top:0;bottom:0;left:0;width:100%;background:#000;opacity:0.65;-moz-opacity:0.65; filter:alpha(opacity=65);');
            
            overLayDiv.setAttribute('class','key_overlay');
            overLayDiv.id = 'key_overlay';
            var _body = document.getElementsByTagName('body') [0];
            _body.appendChild(overLayDiv);
            
            var divcontainer = document.createElement('div');
            divcontainer.id = 'keymailer_formcontainer';
            $(divcontainer).attr('style','display:none;position:absolute;left:50%;top:50%;margin-left:-170px;margin-top:'+(scrolltop-100)+'px;width:340px;float:left;padding:10px;color:white!important;z-index:10001;height:180px;');
            
            var closeButton = document.createElement('a');
            closeButton.setAttribute('href','javascript:key_togglePop(\'key_overlay\');key_togglePop(\'keymailer_formcontainer\');');
            $(closeButton).attr('style','position:absolute;top:15px;right:35px;color:white;');
            closeButton.innerHTML = '<img src="http://nyhetsbrev.bt.no/sitefiles/6/newsletter/close-bg.png" alt="Lukk"/>';
            divcontainer.appendChild(closeButton);
            
            document.body.appendChild(divcontainer);
            var formIframe = document.createElement('iframe');
            formIframe.id = 'key_iframe';
            
            formIframe.src = 'http://nyhetsbrev.bt.no/?c_=BT_KEYMAILER&m_=showKeyMailerForm';
            $(formIframe).attr('style','border:0px;width:320px;height:136px;float:left;overflow:hidden;').attr('scrolling','no').attr('frameborder','0').attr('border','0');
            document.getElementById('keymailer_formcontainer').appendChild(formIframe);

            var frame = document.getElementById('key_iframe');
            frame.src = frame.src + '&category='+categories;
            key_togglePop('key_overlay');
            key_togglePop('keymailer_formcontainer');
        }
	function key_togglePop(element)
        {
              var el = document.getElementById(element);
              el.style.display = (el.style.display == "block") ? "none" : "block";
        }