Comment 2 for bug 406303

For what's it worth, here's an indirect confirmation for this bug for Hardy.

I'm using SysCP and had problems with APS files (which would be reported as "this is not an APS file").

http://wiki.syscp.org/docs/aps-handbook says under "PHP configuration issues" has this to say:
"Users of a 64bit system with PHP 5.2 must enable the PHP exec function in their configuration for the SysCP vHost. That's because in the 64bit version of PHP 5.2 exists a bug, which makes it impossible to open Zip files including more than 509 files. For that reason a fallback has been implemented which relies on the exec function of PHP. The files will be extracted in the temporary directory using unzip. So exec mustn't be in disabled_functions if you use a 64bit system!"

Applying the described fixes indeed made all the "this is not an APS file" messages go away.
This is fully consistent with the existence of the bug in Hardy. (Seeing the zip_open bug was first reported for PHP 5.1.something, this is less than surprising IMHO.)

I'd like to see this make its way within the next week because a long-scheduled hardware upgrade to a 64-bit machine will be effective then, and we may be unable to apply security fixes for PHP software if they are distributed as zip archives with more than 509 files in the root directory, and no workaround.
Not a large chance of happening, particularly since we're going to upgrade to Karmic ASAP, but if it does happen, we're screwed...