Assuming you want to replicate a subset of PEAR-installable packages that are on one machine and you wish to install that same set on another machine, this is one suggested way to get the required details: Use the output of "$ pear list -a" to determine the names of the packages, which versions are installed and what channels they were installed from.
For example (edited for brevity):
Installed packages, channel doc.php.net:
========================================
Package Version State
PhD 0.4.6 beta
Installed packages, channel pear.php.net:
=========================================
Package Version State
PEAR 1.8.1 stable
PEAR_Size 0.1.9 alpha
PHP_Beautifier 0.1.14 beta
PHP_CodeSniffer 1.2.0RC1 beta
PHP_CompatInfo 1.9.0 stable
PHP_UML 0.5.2 alpha
PhpDocumentor 1.4.2 stable
Testing_Selenium 0.4.3 beta
Installed packages, channel pear.phpunit.de:
============================================
Package Version State
PHPUnit 3.3.16 stable
phpcpd 1.1.1 stable