Has anyone experienced an error when doing a maven build?

My project structure is common stuff:
/
/apps
/conf
The filter.xml in /META-INF/vault/filter.xml
<?xml version="1.0" encoding="UTF-8"?>
<workspaceFilter version="1.0">
<filter root="/conf/testproj" mode="merge"/>
<filter root="/apps/testproj" mode="merge"/>
</workspaceFilter>
After doing a maven build (clean, then install) the error is
[INFO] Loading filter from /projects/my-view/src/main/content/META-INF/vault/filter.xml
[ERROR] 1 error(s) detected during dependency analysis.
1 error(s) detected during dependency analysis.
Filter root's ancestor '/conf' is not covered by any of the specified dependencies.
Not sure if the error message makes sense, since I have no dependencies on the view (or ui.apps). This behavior was reported already for the vault plugin 0.5.4.
Interesting is, that if I create a different Maven module, like e.g. ui.content, add a pom-dependency to the view (or ui.apps), manage /conf with that module, then the vault plugin seems to work.
Therefore my question: Is there indeed a dependency error (what dependency are we talking about) or is this a bug similar to what was reported for the vault plugin 0.5.4?