For two bundled functions examples, gmeans works fine, titleCase does not

[mark-watson]

I built the two examples as-provided (note that /Users/markwatson/bin/stardog is mapped as a virtual disk in my Stardog Docker container):
git clone https://github.com/stardog-union/stardog-examples.git
cd stardog-examples/examples/function
../../gradlew compileJava -PstardogHome=/Users/markwatson/bin/stardog
cd bin/main; jar cvf ../../mark.jar *
cp mark.jar $(STARDOG_HOME)/
Inside the Docker container running Stardog:
cd /opt/stardog/server
cp /var/opt/stardog/mark.jar ext/

The gmeans function works fine after restarting the container, the titleCase example throws an error: Unrecognized function: tag:stardog:api:titleCase

I made no code changes. Has anyone else seen this problem?