Vars.prototype.toString = function(pre) {
	var result = '';
	if(pre == null) { pre = ''; }
	for(var i in this) {
		if(this[i] != null && typeof(this[i]) != 'object' && typeof(this[i]) != 'function' && i != 'numVars') {
			result += pre + i + '=' + this[i] + '&';
		}
	}
	if(result.length > 0) result = result.substr(0, result.length-1);
	return result;
}