Dependency sources support appears to require javadoc-resources

I cannot seem to get the <includeDependencySources> support to work. Although I have scoped the dependencies down using various combinations of <dependencySourceIncludes> and <dependencySourcesExcludes>, as well as setting <includeTransitiveDependencySources> to false, no iteration ever succeeds.
Instead, the javadoc:jar goal complains of being unable to find the "javadoc-resources" for a whole slew of dependencies.
None of my projects or dependencies use javadoc-resources. They are all very basic Javascript JARs with minimal configuration.
I noticed that part of the 2.7 release (revision 933380) added support for javadoc-resource bundle aggregation, as well. Is the javadoc-resources search not scoped to the include/exclude list?