Running tests in the browser broken on node 0.12

[danquirk]

Works fine on older versions of node, just started breaking with 0.12, multiple people have hit this:

jake runtests-browser tests=fourslash
Running test(s): fourslash
node tests/webTestServer.js 8888 IE fourslash
Static file server running at
  => http://localhost:8888/
CTRL + C to shutdown
Using browser: C:/Program Files/Internet Explorer/iexplore.exe
child_process.js:961
    throw new TypeError('options argument must be an object');
          ^
TypeError: options argument must be an object
    at normalizeSpawnArguments (child_process.js:961:11)
    at Object.exports.spawn (child_process.js:984:38)
    at Object.<anonymous> (C:\TypeScript\tests\webTestServer.js:256:15)
    at Module._compile (module.js:460:26)
    at Object.Module._extensions..js (module.js:478:10)
    at Module.load (module.js:355:32)
    at Function.Module._load (module.js:310:12)
    at Function.Module.runMain (module.js:501:10)
    at startup (node.js:129:16)
    at node.js:814:3
jake aborted.
Error: Process exited with code 1
    at api.fail (C:\Users\alexcop\AppData\Roaming\npm\node_modules\jake\lib\api.js:336:18)
    at null.<anonymous> (C:\TypeScript\Jakefile:519:42)
(See full trace by running task with --trace)