Debian Tutorials posted a guide about installing the PEAR framework on Debian GNU/Linux

PEAR is a framework and distribution system for reusable PHP components.
1. Install the PEAR framework
get install php-pear

2. Restart apache
/etc/init.d/apace2 restart

3. Install a PEAR package (optional)
pear install Net_Ping-2.4.5

You can install any PEAR package using this command but in this example we'll install the Net_Ping package
4. Here's a sample PHP code to use the Net_Ping package (optional)
require_once [...]

  Installing PEAR framework and packages