Yes, you can unzip, edit and then zip again.
When zipping, the mimetype file must be the first file in the zip, and it must be zipped uncompressed. The other files must follow.
I wrote an Applescript for Mac OS X that does this zipping. I'm sure a batch file for Windows could be written too.
Originally Posted by padman
Thanks for your guide. You're suggesting editing files through an archive editor. Can you first unzip the epub, make the changes and then compile again? I couldn't find any tool that would make this compilation.