How can I zip, gzip or bzip2 a dump or a CSV export? It does not seem to work.
These features are based on the gzencode() and bzcompress() PHP functions to be more independent of the platform (Unix/Windows, Safe Mode or not, and so on). So, you must have PHP >= 4.0.4 and zlib/bzip2 support (--with-zlib and --with-bz2).
We faced PHP crashes when trying to download a dump with MS Internet Explorer when phpMyAdmin is run with a release candidate of PHP 4.2.0. In this case you should switch to the release version of PHP 4.2.0.