When running PEAR manager to install a package (eg, ./pear install Log), if you encounter this error “No handlers for package.xml version 2.0″, it means your PEAR needs upgrading.
The command to upgrade PEAR:
./pear upgrade PEAR
When upgrading PEAR, you might be prompted to upgrade some other dependencies (such as Archive_Tar):
./pear upgrade Archive_Tar
