Univention provides a software component with PHP 5.4 packages for UCS 3.2. With the following instructions the PHP 5.4 component can be activated and the PHP 5.3 packages can be updated to version 5.4. Please keep in mind that some apps (zarafa, kolab) will not work with PHP 5.4.
1. Activation of the PHP 5.4 software component:
ucr set repository/online/component/php54=true
2. Update of the PHP packages to version 5.4:
dpkg -P php5-suhosin