Node.js/formidable error is not handled by form.on('error')

I'm using formidable for uploading files. When the upload fails (e.g., when the uploadDir is not writable) the error is not handled by form.on('error'), instead it's an uncaught exception. How do I handle upload errors? This is basically the sample code from fromidable's Readme, with a non-existing uploadDir and an error handler.

var formidable = require('formidable'),
    http = require('http'),

    util = require('util');

http.createServer(function(req, res) {
  if (req.url == '/upload' && req.method.toLowerCase() == 'post') {
    // parse a file upload
    var form = new formidable.IncomingForm();

    form.uploadDir = '/foo/'; // this does not exist

    form.on('error', function(error) { // I thought this would handle the upload error
      console.log("ERROR " + error);
      return;
    })

    form.parse(req, function(err, fields, files) {
      res.writeHead(200, {'content-type': 'text/plain'});
      res.write('received upload:\n\n');
      res.end(util.inspect({fields: fields, files: files}));
    });
    return;
  }

  // show a file upload form
  res.writeHead(200, {'content-type': 'text/html'});
  res.end(
    '<form action="/upload" enctype="multipart/form-data" method="post">'+
    '<input type="text" name="title"><br>'+
    '<input type="file" name="upload" multiple="multiple"><br>'+
    '<input type="submit" value="Upload">'+
    '</form>'
  );
}).listen(8000);

The error I receive is:

events.js:66
        throw arguments[1]; // Unhandled 'error' event
                       ^
Error: ENOENT, open '/foo/9b4121c196dcf3f55be4c8465f949d5b'