Document Management System

a PHP writen system which can upload an maintain company documents. Put the files into the server and have a user interfase for searching, view, workflow, etc. pretty much like the service offered by <[login to view URL]> We could accept a previously developped application which have the following functions we need: a. register and upload a new document. b. assign rights for view and modify c. design and follow up a workfolw for a document d. make a document obsolet or archive it The documents should be created in microsoft office, open office or any other personal productivity suite. user interfase must be in spanish (mexican desired)