node-http-proxy websocket timeout with Socket.io

For some reason http-proxy causes socket.io based websocket connection reconnect after every 2 minutes. Before reconnection messages are working just fine between client and server. If I bypass proxy, the websocket connection works without reconnections. Proxy configuration is very basic and follows an example from nodejitsu.

var http = require('http'),
  httpProxy = require('http-proxy');

var options = {
  hostNameOnly: true,
  router: {
    'example.com/sockets/': '127.0.0.1:9001'
  }
};

var proxyServer = httpProxy.createServer(options);
proxyServer.listen(80);

I have also tried to change the timeout option in configuration but this does not have an affect to the reconnection problem.

timeout: 120000 // override the default 2 minute http socket timeout value in milliseconds

Software versions: Ubuntu 12.04 server, node.js 0.8.16, http-proxy 0.8.7, socket.io 0.8.7.

This works perfectly on dev Mac (10.8.3) and on Ubuntu desktop 12.04 (virtualbox) but not on server.