Edit word document that is forwarded by a servlet from a webdav server

I have a webdav server but and to edit and save directly to the server I am using this protocol: ms-word:ofe|u|http://url.com/test.docx. But instead of directly using the document url I want to have a servlet that forwards or redirects to the file. When doing this though I get an error message Unexpected error from Microsoft office. Anyone know how I can achieve what I want?