Service Manager 9.20 - Create a PM via WebService

Hi all, i´m trying to create a PM via SM WebService engine but the option to Add a new PM is not beeing presented in the WSDL.

I´m using the table rootcause and i have enabled "add" on the Allowed Actions sections of my WSDL Configuration.

Anyone have any idea on why the add option is not showing on the wsdl ?

I found a comment on the post below saying something about not all objects on the database beeing able to be created/deleted via a service API. Would that be the case? 

/t5/Service-Manager-Service-Center/HP-Service-Manager-web-service-tutorial-sought/td-p/2402985