The Joomla! Community (www.joomla.org) is planning to implement Moodle LMS as certification platform to conduct online exams.
If you have the expertise and time to volunteer for open source project using Moodle, kindly contact me.
Volunteers will be joining the certification program team and need to contribute some hours per week to develop the test system. To appreciate all volunteers, the Certification Project will award badges and all volunteers will be listed here: http://volunteers.joomla.org.