EventEmitter in Vows

var assert = require('assert'),
    EventEmitter = require('events').EventEmitter,
    sys = require('sys'),
    vows = require('vows');

vows.describe("Vows").addBatch({
    "Creation": { 
        topic: function () {
            var e = Object.create(EventEmitter.prototype);
            process.nextTick(function () {
                e.emit('error', "xxx");                
            });
            return e;
        },
        'should be': function (e, topic) {
            assert.equal(e, "xxx")
        }
    }
})
.export(module);