window.onload = function() {
    if (document.getElementById) {
        var linkContainer = document.getElementById('fm-intro');
        if (linkContainer) {	//this page has a form on it
	        var toggle = linkContainer.appendChild(document.createElement('a'));
	        toggle.href = '#';
	        toggle.appendChild(document.createTextNode('(Hide optional fields)'));
	        toggle.onclick = function() {
	            var linkText = this.firstChild.nodeValue;
	            this.firstChild.nodeValue = (linkText == '(Hide optional fields)') ? '(Display optional fields)' : '(Hide optional fields)';
	            var tmp = document.getElementsByTagName('div');
	            for (var i = 0; i < tmp.length; i++) {
	                if(tmp[i].className == 'fm-opt') {
	                    tmp[i].style.display = (tmp[i].style.display == 'none') ? 'block' : 'none';
	                }
	            }
	            return false;
	        }
    	}
    }
}