transferring outboubd deliveries between two systems

Hi Experts,

we are trying to transfer the outbound deliveries created in system A to system B through idocs using standard inbound FM idoc_input_delvry FM in system B. when we do that the idoc is getting into error saying " document with number XXXXXXXX does not exists in the system". It seems the std inbound FM does not create a new outboud delivery, it only changes the existing one.

Is there any way to overcome this problem.

thanks

sankar