I recently updated my server to PHP 5.4 and discovered that I was no longer able to restart the PHP-FPM service using the regular:
$ /etc/init.d/php5-fpm restart
or
$ service php5-fpm restart
I went to the official Debian GIT repository for the PHP 5.4 beta package and found the following differences between the init scripts (here is the one from Dotdeb):
Replacing my init script with the one from the official beta package solved the problem. I wonder what export ZEND_DONT_UNLOAD_MODULES=1 does wrong.