Zend Framework's Bughuntday and it turned out to be a huge success, as mentioned by Chief Architect Matthew Weier O' Phinney on Zend's DevZone website.
Over a hunderd bugs were squashed leading up to the release of Zend Framework 1.9.3.
What is Bughuntday ?
Bughuntday is actually a term to indicate that on a specific day (or days), lots of developers are focussing their attention to fix bugs, often reported by users in a bug tracking tool (like Jira, Mantis or Bugzilla).
Since lots of users have submitted issues and only a few developers have time to investigate them, extra help is always welcome to clear a backlog of reported issues.
So, each year a "Bughuntday" is scheduled to have many developers fix issues in a relative short timeframe.
You can help !
Fixing bugs for Zend Framework is a very good way to learn best coding practices or parts of the framework you're not familiar with.
Go over to the Zend Framework Issue Tracker and look for bugs that are still open.
If you already signed the Zend CLA, you're good to go. If you haven't done this, now is a good time to do so.
Get the latest revision from http://framework.zend.com/svn/framework/standard/trunk/, which includes the library, unit tests, external libraries and documentation.
In case of emergency
If you're stuck, or you have created a patch to fix an issue, head over to #zftalk.dev on IRC (freenode) where you can ask for help.
The Zend Framework Bughuntday is held each third Thursday and Friday of the month and each month prizes are given to the top 3 fixers.
If your company uses Zend Framework, see if you cannot make it a company thing. The quality improvement of Zend Framework will be a great benefit for your company as well.