XAMPP for Mac does come with PEAR but it is NOT configured.

Update PEAR
sudo su - [Enter root password]
cd /Applications/xampp/xamppfiles/lib/php/pear
sudo php pearcmd.php channel-update pear.php.net
sudo php pearcmd.php install PEAR
sudo php pearcmd.php install Log
sudo php pearcmd.php list

add PEAR to the php.ini include_path
Edit /Applications/xampp/etc/php.ini (include path is at the very end of the php.ini file)

include_path = “.:/Applications/xampp/xamppfiles/lib/php:/Applications/xampp/xamppfiles/lib/php/pear”

To install a package
Type
sudo su [Enter root password]
cd /Applications/xampp/xamppfiles/lib/php/pear
pear install pear/PACKAGE_NAME

Thats it, good luck.