var CF_defaultComment = "Enter your comment here...";
var CF_defaultAuthor = "Your name";
var CF_defaultEmail = "Your email (not displayed)";
var CF_defaultUrl = "Your website (optional)";
	
function CF_setDefaults(set) {
	var func;
	if(set) {
		func = function (element, value) { CF_setFromTo(element, "", value);}
	} else {
		func = CF_resetDefault;
	}
	func(document.commentform.comment, CF_defaultComment);
	func(document.commentform.author, CF_defaultAuthor);
	func(document.commentform.email, CF_defaultEmail);
	func(document.commentform.url, CF_defaultUrl);
	return true;
}

function CF_resetDefault(element, value) {
	CF_setFromTo(element, value, "");
}

function CF_setFromTo(element, from, to) {
	if(element && (element.value == from)) {
		element.value = to;
	}
}

CF_setDefaults(true);