The PHP-XMLRPC library base package, version 2.1 or later, is a prerequisite for the extras packages.
A working php setup is of course needed.
The base library is tested to work with php versions ranging from 4.0.5 to 5.2. Please note that not all library features are available for every PHP version. The "curl" php extension is needed to support https calls. The "json" and "xmlrpc" php extensions do not interfere with the operations of either the base library or extras.
A complete testsuite has not yet been implemented for every component that is part of the extras. This prevents complete regression tests to be carried out against all php versions. If you encounter any quirk, especially with old php installs, please report it on the project development pages.