bjori@lindsay:~$ pear install http://doc.php.net/phd/PhD-0.2.2.tgz
downloading PhD-0.2.2.tgz ...
Starting to download PhD-0.2.2.tgz (26,418 bytes)
.........done: 26,418 bytes
install ok: channel://__uri/PhD-0.2.2
bjori@lindsay:~$ mkdir build && cd build
bjori@lindsay:~/build$ phd -d /path/to/phpdoc/.manual.xml

Getting the code:

$ cvs -d:pserver:cvsread@cvs.php.net/repository co phd

Install and run from CVS:

$ cd phd
$ pear install -f package.xml
$ phd -d/path/to/phpdoc/.manual.xml

Alternately you can (although not recommended) run PhD directly from CVS, without needing to install it:

$ cd phd
$ php build.php -d/path/to/phpdoc/.manual.xml