Return value or Output parameter of stored proc

Hello folks,
              I am writing a stored procedure in SQL server. Every thing
seems to work fine.But I am not getting the output or return value.

   MyCom :=  CoCommand.Create;
   MyCom._Set_ActiveConnection(cs);
   MyCom.Set_CommandText('test');

MyCom.Parameters.Append(MyCom.CreateParameter('Return_Value',adBSTR,adParamReturnValue,10,adEmpty));

MyCom.Parameters.Append(MyCom.CreateParameter('@IN',adBSTR,adParamInput,10,'h'));

MyCom.Parameters.Append(MyCom.CreateParameter('@OUT',adBSTR,adParamOutput,10,adEmpty));

   MyCom.Execute(a,EmptyParam,adCmdStoredProc);
   x := MyCom.Parameters.Item['@IN'].Value;
   y := MyCom.Parameters.Item['@Return_Value'].Value;
   z := MyCom.Parameters.Item['@OUT'].Value;

I get only @IN's value.

       What shld I do.Please tell me your suggestions

Thanking you,

Manju.