NotSerializableException: org.jbpm.bpmn2.xml.ProcessHandler$1 when trying to serialize CancelActivity action

Guvnor fails to create/serialize a package when it contains a process that uses Boundary Events with CancelActivity = true.

Checking the ProcessHandler class, on line 475, it creates a new Action to cancel the current node instance. The resulting inner class does not implements Serializable, causing the following exception: java.io.NotSerializableException: org.jbpm.bpmn2.xml.ProcessHandler$1.