I haven't install pear in my PC,instead I download the packages and unzip them to "libs" dictionary in my web-app.the structure of dictionary of my web-app is roughly like this:
web-app
+-/backend
+-/libs
+-/peardb
+-pear.php
+-pear5.php
+-mdb2.php
+-/mdb2
The application works fine in my two PCs,but throws "Cannot redeclare class mdb2_error" error while it running in virtual host.
Using
include_once/require_oncecan usually solve this problem.