Add 0ACTIVITY infoobject in hierarchy

Hello Gurus,

We have a standard hierarchy WBSH  which extract data from 0WBS_ELEMT_WBSH_HIER datasource. It is giving me tree structure till WBS i.e.

0Project->0Network->0WBS. Now i want to add 0Activity in tree after 0WBS. How can i achieve this? Do I need to create generic hierarchy datasource for this or is their any way to add 0Activity infoobject as child node to 0WBS in WBSH. I have created generic datasource having values for all infoobject in one row i.e 0Project->0Network->0WBS->0Activity but i need it in hierarchy structure i.e 0Project

                                                                                                                                  -> 0Network

                                                                                                                                            -> 0WBS

                                                                                                                                                      -> 0Activity.

Regards,

Vishal