I'm attempting to enable the memberof plugin in version 1.2.11 on CentOS 6.x.  Unfortunately, it don't seem to be able to get the plugin enabled and functioning.  With plugin logging enabled, I see other plugins logging their startup and functionality, while I see nothing from the memberof plugin despite having enabled it in the configuration.  I've tried a variety of different logging levels and configurations, but it just doesn't seem like the code is firing at all.  Can anyone suggest what I might be doing wrong or how to further diagnose the issues?