Dynamic receiver Determination for Sync Scenario??

Hello Experts,

I have a SOAP -> Xi -> R3 sync scenario i,e, R3 to send back response to SOAP client.

Also I need the Dynamic receiver determination.

When I try to create the Interface Mapping, I get the error:

"Interface modi are different. "

Source interface MI_My_sync_iface is synchronous.

Target interface ReceiverDetermination | http://sap.com/xi/XI/System is asynchronous

I coud find few threads on forum related to this but i think there is no clear solution provided.

I do not wanna use BPM.

Please suggest.

Thanks in Advance!

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