The patch for configure allowed for a past upgrade of zlib by checking for version 1.1.3 or 1.1.4 rather than just for 1.1.3. zlib 1.1.4 is now outdated, so the port simply fails to use zlib. I've successfully fixed this on my own system by adding another version to check for. Really the check should just be for version >= 1.1.3, but my shell scripting skills are limited (thanks to perl), and I'm not sure how to do a reasonable version comparison. Fix: My solution (inadequate, as noted) was to replace patch-configure with the following. This works for the time being, but will break again when zlib is next updated.
Responsible Changed From-To: freebsd-ports-bugs->jylefort Take.
State Changed From-To: open->closed Committed with a few modifications, thanks!