return the transaction + pass it to the callback

lib/sequelize.js

@@ -376,8 +376,13 @@ module.exports = (function() {
   Sequelize.prototype.transaction = function(_options, _callback) {
   Sequelize.prototype.transaction = function(_options, _callback) {
     var options     = (typeof _options === 'function') ? {} : _options
     var options     = (typeof _options === 'function') ? {} : _options
       , callback    = (typeof _options === 'function') ? _options : _callback
       , callback    = (typeof _options === 'function') ? _options : _callback
+      , transaction = new Transaction(options)
 
 
-    callback(new Transaction(options))
+    Utils.tick(function() {
+      callback(transaction)
+    })
+
+    return transaction
   }
   }
 
 
   return Sequelize
   return Sequelize