HELP. Returning REF CURSOR from Oracle Stored Procedure

Hi.  I created a Stored Procedure in Oracle that returns a variable type
REF CURSOR  (it returns a table)

Im trying to execute the SP using a TStoredProc ,  I configured the
parameter to:

datatype:  ftCursor
ParamType : ptInputOutput

I execute the sp as follows:

I also tried with : := True

I'm getting the error:  EDBEngineError 'Operation Not Applicable'
So I checked the SP and its OK, I execute it normally from a Visual
Basic app.

I'm using  Oracle
Delphi 6   (enterprise edition. trial version)
BDE :  5.01

Help appreciated. thanks!