When registering an event listener, you have to additional attribute "class" instead of "type".

Using "type" has no effect. It turns out it is supposed to be 'class'. Also figured it here - http://stackoverflow.com/questions/15007281/add-extra-fields-using-jms-serializer-bundle
Merge pull request #360 from epicwhale/patch-1

Documentation Fix: When registering an event listener, you have to additional attribute "cl...