In a recent symfony project a client requested a robust search tool to help their users find what they were looking for quickly and easily. Our solution was to implement the sfLucenePlugin which is powered by the very robust Zend Search Lucene Library in the Zend Framework. Installation and customization was a snap thanks to the automation of symfony and the plugin documentation.
Over the next several weeks we beta tested the new search feature and didn't experience any problems. After thorough testing by a few dozen users we decided that the application was ready for prime time. It didn't take us long to regret that decision.
Within a few hours of launch a very nasty bug showed up and brought our entire application to it's knees. No graceful recoveries, no helpful error messages, just a dead site.
After a bit of research we found that the problem was related to a bug present in version 1.5 of the Zend Framework. The fatal error resulted in an ugly "XXX.del is not readable" exception and, in the context of our application, all subsequent requests resulted in the same fatal error. If you care to read more about the root cause of the problem, it's discussed in detail on the Zend Framework Forum.
The Zend Framework was patched to resolve this issue back in version 1.6 but unfortunately sfLucenePlugin still ships with the buggy 1.5 version. Since the sfLucenePlugin hasn't been updated since May 2008 we decided to manually replace the contents of "sfLucenePlugin/lib/vendor/Zend/Search/" with the updated library files found in version 1.7 of the Zend Framework, located in "library/Zend/Search/".
Since then, things have been running quite smooth and we have not noticed any incompatibilities between sfLucenePlugin and Zend Search Lucene 1.7. Hopefully this suggestion will save other developers from yanking their hair out over the same issue.