Control Sender Address when Sending PO SAP

PO by e-mail: how to control sender address
My PO's are now being send by e-mail. Unfortuntely, it seems impossible to control the sender of the e-mail; When the timing is on '4', the sender will be the employee who did the final release, when on '1', the sender will be the user who schedules the RSNASTOO job. I want the user who created the PO to be the sender of the PO.

The following may help you solve your problem.

I am using the following in my PO Sapscript

/: DEFINE &W_USER_EMAIL& = ' '
/: PERFORM GET_USER_EMAIL IN PROGRAM ZVENDOR_FAX_EMAIL
/: USING &EKKO-ERNAM&
/: CHANGING &W_USER_EMAIL&
/: ENDPERFORM
= ,,,, &'Created by: 'W_USER_EMAIL&

and the following in PROGRAM ZVENDOR_FAX_EMAIL

FORM GET_USER_EMAIL TABLES IN_TAB STRUCTURE ITCSY
out_tab structure itcsy.

data: L_user like USR21-BNAME.
data: L_persno like usr21-persnumber.
data: L_user_email like ADR6-SMTP_ADDR.

* gets User name
READ TABLE IN_TAB WITH KEY 'EKKO-ERNAM'.
IF SY-SUBRC EQ 0.
CLEAR: L_USER, L_USER_EMAIL, L_persno.
L_user = IN_TAB-value.

* read user master
Select single PERSNUMBER from usr21 into L_persno
where bname EQ L_user.
*e-mail found
if sy-subrc eq 0 and L_persno ne space.
select smtp_addr from adr6 into L_user_email
up to 1 rows
where persnumber eq L_persno
and date_from le sy-datum.
endselect.
if sy-subrc eq 0 and L_user_email ne space.

read table out_tab with key 'W_USER_EMAIL'.
if sy-subrc eq 0.
move L_user_email to out_tab-value.
modify out_tab index sy-tabix.
endif.
endif.
endif.
endif.
endform. "GET_USER_EMAIL