Allows dash characters in subdomains

server.js

@@ -134,7 +134,7 @@ function maybe_bounce(req, res, sock, head) {
         var client_req = http.request(opt, function(client_res) {
             // write response code and headers
             res.writeHead(client_res.statusCode, client_res.headers);
-            
+
             client_res.pipe(res);
             on_finished(client_res, function(err) {
                 done();
@@ -221,7 +221,7 @@ module.exports = function(opt) {
         var req_id = req.params.req_id;
 
         // limit requested hostnames to 63 characters
-        if (! /^[a-z0-9]{4,63}$/.test(req_id)) {
+        if (! /^(?:[a-z0-9][a-z0-9\-]{4,63}[a-z0-9]|[a-z0-9]{4,63})$/.test(req_id)) {
             var err = new Error('Invalid subdomain. Subdomains must be lowercase and between 4 and 63 alphanumeric characters.');
             err.statusCode = 403;
             return next(err);