CProject evaluation table: How to get project-related task confirmation

Hi everybody.

I'm working on cproject and this is my problem:

In my report i can get details related to an assigned project (i know Project guid) in this way:

CALL FUNCTION 'BAPI_BUS2172_GET_DETAIL'

EXPORTING

project_definition_guid = project_guid

IMPORTING

es_project_definition_detail = es_project_definition_detail

TABLES

et_name = et_name

et_status = et_status

return = return.

This bapi let me know the total confirmation status of my project ( this value is contained in the ACT_WORK_EFFORT of the standard data base table DPR_PROJECT ).

I would like also to get the confirmation status of each task related to this project ......

i think that these values are contained in the field ACT_WORK_EFFORT of the table DPR_TASK .... but i'm not able to select all and only tasks related to a single progect ....

Thanks,

FG