function validate_com_free_att_FormFields(fields)	{
	var error = false;
	//for each (var field in fields) {
	for (var i = 0; i < fields.length; i++) {
		field = fields[i];
		field_value = document.getElementById(field).value;
		if(jQuery.trim(field_value.toString()) == '') {
			//does not work
			//$(field).addClass('invalid_field');
			//so call it directly
			jQuery.className.add(document.getElementById(field), 'invalid_field');
			error=true;
		} else {
			//does not work
			//$(field).removeClass('invalid_field');
			//so call it directly
			jQuery.className.remove(document.getElementById(field), 'invalid_field');
		}
	}

	return error;
}