Delivery Schedule Change triggers PO change event.

[virendradapt]

Hello,
 
Looking for help/suggestions...
 
I have a task which is defined for Scheduling agreement object(BUS2013).
 
Delivery Schedule "changed" should be the triggering event for the
task(business requirement).
 
When the Delivery Schedule is changed(ME38), it triggers event "Changed" in
Purchase Order object(BUS2012).
( Event log shows PO obj(BUS2012) with object key as Scheduling agreement
number ! )
 
The is problem is task(obj BUS2013) is not being triggered by event(BUS2012)
due to obj type mismatch.
During binding only warning given suggesting semantic problems could exist,
but deactivates event linkage,
(possible due to above reason ).
 
All inputs would be appreciated.
 
Thanks,
Virendra.