Here is another tool to edit the metadata in PDFs before you upload them to the eDGe's library:
BeCyPDFMetaEdit http://www.becyhome.de/becypdfmetaed...iption_eng.htm
It seems to be more handy for this purpose than the jPDFTweak tool mentioned before.

I suppose, these tools will only work for unprotected PDFs, but I've never tried it. For protected documents, you have to change the information as described by borisb before (on the eDGe library: Info->Edit).