Asynchronous to Synchronous Bridge with SAP IDocs

I have a web service provider that ultimately posts the contents of the message as an IDoc in a SAP system. IDocs are posted asyncronously, and I would like to get the status data of the IDoc back to the response of the web service. problem is, it may be a few seconds under heavy loads before the IDoc status is updated.

Has anybody else come up with an elegant solution concerning how to do this?