I am going to shut down the Nexus instance at https://maven.objectstyle.org/nexus/ . There's so much open source infrastructure out there, that running your own Maven repo seems wasteful, and what's worse it creates security issues without proper maintenance.
This server was used for Cayenne builds, as a virtual repo combining Maven Central and an internal repo with artifacts that are not available on Central. Cayenne 5.0 no longer requires that second part, and for the earlier versions I placed those artifacts in a static directory under Apache at https://maven.objectstyle.org/repos/cayenne-deps/ . So Nexus is going down now. Andrus