This small bit of python allows you to create zipfiles or add files to existing zipfiles with relative path names containing '..' or double periods.
WinZip 16.5 will warn you about this as a security risk in the GUI and the command line, but both can be overridden, the latter with -yO.
Mileage may vary with different zip implementations and versions.
Nix Unzip 6.0
7Zip 4.65 Windows XP Inbuilt ZIP functionality (also raises a security error if you use backslashes ..\ etc)