File Upload in GWT in a Special Case

Question

I am doing a software for a document system. In this system when a user completes a document and want to save it, the document will be uploaded directly to server without the user action.

This system uses COM/ActiveX to facilitate user using native editors.

Ok, my problem is: suppose I have a file say d:/notepad.txt. Using classical method a user can browse the file and upload it. I can do that with apache commonio and GWT FormPanel and FileUpload. But if I know the filename (d:/notepad.txt), is there any way to upload the file directly to server without the user having to browse the file.

I am currently doing this by the ActiveX componenet calling some HttpUpload methods with POST. But that does not maintain session.

Thanks