First, let’s grab the PEAR installer:

curl http://pear.php.net/go-pear > go-pear.php
sudo php -q go-pear.php

Press enter to use default until you get to the file layout and edit the first to be /usr/local

1. Installation prefix ($prefix) : /usr/local
2. Temporary files directory     : $prefix/temp
3. Binaries directory            : $prefix/bin
4. PHP code directory ($php_dir) : $prefix/PEAR
5. Documentation base directory  : $php_dir/docs
6. Data base directory           : $php_dir/data
7. Tests base directory          : $php_dir/tests

Press Enter to continue and Y to install

PEAR_Frontend_Web-beta, PEAR_Frontend_Gtk2, and MDB2

Hit Y to let PEAR update your include path

That’s it! You should be able to type in pear version to see PEAR installed.