function initCollapsibleElements() {
	imageArrowClosed = new Image(13,12);
	imageArrowClosed.src = "aufklapp_zu.gif";
	imageArrowOpen = new Image(13,12);
	imageArrowOpen.src = "aufklapp_offen.gif";

    // find all collapsible elements containers
    var index = -1;
    var ceContainers = new Array();
    var allDivs = document.getElementsByTagName("div");
    var ceLink = new Array();
    var j=0;
    for(var i=0; i<allDivs.length; i++) {
    	if (allDivs[i].className == 'expandLink') {
    		ceLink[j] = allDivs[i];
    		var ceContent = document.getElementById(ceLink[j].id + "_content");
    		ceContent.className = 'expandContent';
    		(function (ceContent,ceArrowId) {
    			ceLink[j].onclick = function() {
    				var ceArrow = document.getElementById(ceArrowId);
	    			if (ceContent.style.display == 'none') {
	    				ceContent.style.display = 'block';
	    				if (ceArrow) {
	    					ceArrow.style.backgroundImage = 'url("'+imageArrowOpen.src+'")';
	    				}
	    			} else {
	    				ceContent.style.display = 'none';
	    				if (ceArrow) {
	    					ceArrow.style.backgroundImage = 'url("'+imageArrowClosed.src+'")';
	    				}
	    			}
    			}
    		}) (ceContent,ceLink[j].id+"_arrow");
    		if (j==0) {
    			ceContent.style.display = 'block';
    		} else {
    			ceContent.style.display = 'none';
    		}
    		j++;
    	}
    }
    for(var i=0; i<ceLink.length; i++) { // add arrows
		ceLink[i].className = '';
			newInnerHTML = '<div class="expandArrow" id="'+ceLink[i].id+'_arrow"';
		if (i==0) {
			newInnerHTML = newInnerHTML+' style="background-image: '+"url('"+imageArrowOpen.src+"');"+'">';
		} else {
			newInnerHTML = newInnerHTML+'>';
		}
		newInnerHTML = newInnerHTML + '&nbsp;</div><div class="expandLink">'+ceLink[i].innerHTML+'</div>';
		//ceLink[i].innerHTML = '<div class="expandArrow" id="'+ceLink[i].id+'_arrow">&nbsp;</div><div class="expandLink">'+ceLink[i].innerHTML+'</div>';
		ceLink[i].innerHTML = newInnerHTML;
    }
}