Auto mail trigger to next level till final release after initiator release in PR, PO & Contract

[Rana1131]

Hi Gurus, 

1. Auto mail trigger to next level till final release after initiator release in PR, PO & Contract. Different custom mail body for PR, PO and contract.                                                                                                                          2. Weekly mail reminders to approving authority, whose is having pending PR, PO & Contract. information about the item history of PR e.g. Last PO no, date, rate & current stock.
3. How to integrate the intimation thru SMS.
Note – In SAP, we have different PR Type, PO Type & Contract Type. So, each number will reflect in mail subject and body to next level authority. Final approving authority release ack. will go to initiator mail inbox for information.

Iam a Abap consultant . i have the above auto mail - sms task for PR, PO and contract. Can you please tell me how to approach this ? Is it done with a BADI? Enhancements in me54n, me35, me28  ? or through Extended Notification Workflow ?   can this issue be resolved without Workflow ? or it will require both enhancement + workflow ?