WF: limit the tasks of the SWN_SELSEN program

Hello,

I am setting up a workflow (copy of WF_PO_REL) for the validation of purchase orders, and I use 'Extended notification (Tcode : swnconfig , Program : SWN_SELSEN)' for the notification of users by email, like that each user who receives a notification in workplace = he receives a notification by email .

the problem is that after launching the program it sent notifications of other tasks.

How can I limit the sending of mails by this program only for the tasks that I defined in SWNCONFIG?

Thanks,