Thanks for the reply.my case is .. : i have more roles to be added in my appln.example when a user is created the option box list out the " USER TPYE " (Profesor,student,staff,external).In that i want to add some more types like (Department head,lecture,etc) and also the access level for each level.
Dinesh the user type is local to dotlrn and dotlrn is a vertical application built on the modules of openacs. You must try to use the approach followed in the dotlrn create scripts in your application. But I would suggest you could use a simpler approach for your application by directly using the groups api for handling roles.