Copied variable "ActorId" to process variable doesn't work

step1: define a process variable "pv_actor" ; step2 : in the human task , set the output: ActorId as a output param step3: mapping the ActorId to the process variable "pv_actor" ; step4: in the script task: set : System.out.println("process variable :" + pv_actor); What i tried this because we used it in jbpm5.4 and it worked well , and now also it's mentioned in the v6.1 guide : Chapter 6. Processes 6.3.3. User task Result mapping: Allows copying the value of result parameters of the human task to a process variable. Upon completion of the human task, the values will be copied. A human task has a result variable "Result" that contains the data returned by the human actor. The variable "ActorId" contains the id of the actor that actually executed the task.