Problem with Local File Identification in RFC

Dear all,

We are working on a scenario where we have to integrate an external application with SAP system. The external application would use SAP DMS as document repository; It will send us a local file path and we have to upload the document located in that path as an attachment to a DMS Document Info Record. We have designed a wrapper RFC for this purpose, which encapsulates the standard Fm BAPI_DOCUMENT_CREATE2. This BAPI takes a file path input under table parameter DOCUMENTFILES. Problem is, when we are running the RFC from SAP GUI, the document info record is created correctly with the document as attachment, but when we invoke the RFC from the external application, the process fails and we get an error message stating:"Error while checking in Original Files". We debugged the scenario and found out that, while running under SAP GUI, the BAPI is able to identify a GUI Link, and hence succeeds; but while calling from the external application, the BAPI fails to find a GUI Link, tries to start a FTP Server using RFC Destination SAPFTP, and fails. So, obviously, the BAPI is not able to parse the local file path because of non-existence of GUI Link. So,in this regard, my question is: is there no way that we can pass a local file path from an external application to SAP, and get the same identified and get the document uploaded? Is there any alternative to our approach?

Awaiting answers.

Regards,

Sid