function clearField(field, text) {
	if (field.value == text) { field.value = ""; }
	return;
}

function fillField(field, text) {
	if (isblank(field.value)) { field.value = text; }
	return;
}

function isblank(x) {
	var blank = true;
	for (i = 0; i < x.length; i++) {
		if (x.charAt(i) != ' ') { blank = false; }
	}
	return blank;
}

sfHover = function() {
	var sfEls = document.getElementById("nav").getElementsByTagName("LI");
	for (var i=0; i<sfEls.length; i++) {
	sfEls[i].onmouseover=function() {
			this.className+=" sfhover";
		}
		sfEls[i].onmouseout=function() {
			this.className=this.className.replace(new RegExp(" sfhover\\b"), "");
		}
	}
}
if (window.attachEvent) window.attachEvent("onload", sfHover);