function setFieldValue(fieldRef, str) {
	// clears field when user clicks in, 
	// and resets to default str when user clicks out 
	// with no value in the field.
	obj = eval(fieldRef);
	if (obj.value == str) {
		obj.value = "";
	}
	else if (obj.value == "") {
		obj.value = str;
	}
}