Ear plugin dependencies

I am trying to build an Ear using the Ear plugin. Documentation on this plugin says simply:

49.4. Dependency management
The Ear plugin adds two dependency configurations: deploy and
earlib. All dependencies in the deploy configuration are
placed in the root of the EAR archive, and are not transitive. All dependencies in the
earlib configuration are placed in the ‘lib’ directory in the EAR archive and
are transitive.

Sounds simple enough but I find it doesn’t work as I expect. I have one dependency that I want included in the EAR. Either the deploy or earlib configs would meet my needs in this case, but it doesn’t seem to work. If I change the config on this dependency from compile to deploy or to earlib, my code no longer compiles.

It seems to work if I add BOTH an earlib and a compile config on this dependency but I haven’t had to list dependencies twice with other plugins. Is this by design?