Hi Riadh Azzouz, perhaps the use of Event Listeners would do what you are looking to accomplish. It would be useful to know which product and version you are using exactly and possibly a little more specific detail describing your requirements.
Riadh Azzouz I apologize. This forum is listed as Alfresco Process Services (APS) and Activiti. Our Open Source product is Activiti and we have people using Activiti 5, 6 and now, our latest version, Activiti 7. Our commercial product is Alfresco Process Services (powered by Activiti) (APS), which is based on Activiti 5.