Name of the Badi used in txn O3O_RT01

Dear All

I have to validate some fields and insert a drop down in text field in header section of txn O3O_RT01 in ECC6.0.

I am not able to find out BAdi  used there.

Can anybody tell the Name of the Badi used in txn O3O_RT01?

Regards

Amit Agarwal