how to find user eixt for MD04 transaction

Hi

I came to know that for MD04 transaction:

User exit: M61X0002

Function module exit EXIT_SAPLM61R_001 (User Exit for Evaluation PP-MRP Material Requirements Planning)

Include: ZXM61U03

But when I tried to search user exit from <b>SMOD</b> transaction

or with <b>"CALL CUSTOMER-FUNCTION</b>" I could not able to trace the above exit name.

I am trying to find it in SAP version ECC5.0.

Is exit is vertion dependent or what ?

Can any body please explane me how to find the user exit for MD04 transaction

Thanks in advance.

Ramana