Augustine's Letters and Confessions has Latin morphology, but is missing the supports-lbs-morph+la trait. This prevents it from being supported in a morph search.
Another bug was reported in the Logos 5 forum, which suggests that upgrading from an old 5.0 installation straight to 5.1b prevents Logos from applying the trait to Perseus and the other resources. I'm going to guess that the bug occurs if the Perseus resources are updated to their new versions in 5.0, before 5.1 is installed.
