I can’t follow that explaination as I don’t see any patch in the ark version shipped by ubuntu & netrunner. The debian jessie version has a patch to fix issues with zip creation in general with infozip.(maybe also because of older unzip in repo)
I know that unzip in the current trusty repo has problems with umlaute but not passwords. You could try upgrading to the unzip version provided by utopic to try if unzipping works with it: http://packages.ubuntu.com/utopic/unzip
PS: Added comment on kde bugtracker.