running Plex Media Server Version 0.9.12.4.

I am running Plex Media Server Version 0.9.12.4. In reading the release announcements 0.9.12.2 was supposed to "read sort titles from ID3 tags in local media agent".
I have a number of files which contain "sort titles", but Plex isn't recognizing any of them. I use MetaZ to set my ID3 tags, and all of my files have their data set locally. I confirmed that this tag is being read correctly in iTunes.
"Local Media Assets (Movies)" is set as my first agent. I have done a force refresh with no luck. I have also tried it with brand new additions to the library, and Plex isn't picking them up.
Is there something I need to do in order to have this work correctly? Any advice is appreciated.