If you try and compile APD on PHP 5.3, you may get an error similar to the following.
error: 'struct _zend_compiler_globals' has no member named 'extended_info'make: *** [php_apd.lo] Error 1
This can be solved by modifying a few of the APD files. To do this, you need to download the APD archive file and uncompress it.
Then make the changes as detailed on the PHP bug tracker. Once this is done, it should install as normal.
phpize ./configure make sudo make install
APD should now be installed.