BAPI_PROJECT_MAINTAIN : Fill in all the required fields

Hi Experts,

I am trying to create a WBS element under a proj definition using BAPI_PROJECT_MAINTAIN. I get error as : Fill in all the required fields.

I have filled I_PROJECT_DEFINITION with,

PROJECT_DEFINITION , DESCRIPTION , BUS_AREA.

I_METHOD_PROJECT WITH,

REFNUM OBJECTTYPE                       METHOD                           OBJECTKEY

0000001  WBS-ELEMENT                     CREATE                            "SOME VALUE

0000000                                               SAVE

I_WBS_ELEMENT_TABLE WITH,

WBS_ELEMENT              PROJECT_DEFINITION       DESCRIPTION BUS_AREA.

And when executed in SE37, I get error Fill in all the required fields.E055(00).

I have googled for missing field. Some said, to keep PROFIT_CTR as DUmmy.But when I do this I get : profit center 0010/dummy doesnt exist.

Any pointer, please help.

Thanks,

Anil