PHP Warning: PHP Startup: Unable to load dynamic library 'yaf.so' code example

Example: php warning: php startup: unable to load dynamic library

It means there is an extension=... or zend_extension=... line in one of your php configuration files (php.ini, or another close to it) that is trying to load that extension : ixed.5.2.lin

Unfortunately that file or path doesn't exist or the permissions are incorrect.

Try to search in the .ini files that are loaded by PHP (phpinfo() can indicate which ones are) - one of them should try to load that extension.
Either correct the path to the file or comment out the corresponding line.