Install with classifier does not install pom

I have a project wich I need to build only specifying a classifier (in detail: a war project which I need to build with different profiles to include different
configurations. So I set up different filters and the package produces different classified wars).
When I install the artifact, I've got the attached artifact installed but the pom is NOT installed.
The log says "No primary artifact to install, installing attached artifacts instead".
It's maybe related to MINSTALL-18 as it seems the mojo does not recognize the presence of a primary artifact and goes to install the attached artifacts (without installing the POM).
Don't know if this is really a bug or if I am trying a strange/not valid project configuration (a project without a primary artifact).