Hello,
I am facing the same issue, and I think that I know why it is appening but I don't know what else I could do.
In the BADI CRM_ORDERADM_H_BADI, method CRM_ORDERADM_H_MERGE, I used FM CRM_ORDER_READ to get the information of the activity, and the the FM CRM_ORDER_MAINTAIN to modify the activity (add a text).
When I check the call stack, I can see that FM CRM_ORDER_MAINTAIN is already call before and I think that the program check if the FM is not called before otherwise it send a shortdump.
My problem is that I want to use this FM to modify the activity, is there any solution to avoid this problem ?
Thank you.