Strange .pause() behaviour for http client response stream

node-get.js

var fs = require('fs'),
    http = require('http');

var ws = fs.createWriteStream('/tmp/get.png',{flags:'w'});

var reqOpts = {
  method: 'GET',
  path: '/images/nav_logo83.png',
  host: 'www.google.ca'
};
var req = http.request(reqOpts, function (res) {
  var total = 0, total2 = 0;

  console.log(res.headers);
  res.once('error', function (err) {
    console.log(err);
    process.exit(1);
  });
  
  res.pause(); // this doesn't work

  res.on('data',function (chunk) {
    total += chunk.length;
    console.log("UNPAUSED chunk len "+chunk.length);
  });
  
  res.pause(); // this doesn't work either

  setTimeout(function () {
    console.log("\nproceeding\n");
    res.on('data', function (chunk) { total2 += chunk.length; console.log("chunk write len "+chunk.length); ws.write(chunk); });
    res.once('end', function () {
      console.log("END",total,total2);
      ws.end();
      res.removeAllListeners('data');
    });
    res.resume();
  }, 1000);
});
req.once('error', function (err) {
  console.log(err);
  process.exit(1);
});
req.end();