mountvolume myExt3VolumeName yields something like
successfully mounted myExt3VolumeName at ‘(null)’

so it’s not accessible. A second mountvolume myExt3VolumeName tells me it’s already mounted; a mountvolume -umount (or is it -unmount?) myExt3VolumeName says it is not mounted.

Is this a known issue?

I’m running Haiku on real hw, I compiled it just the way mentioned in one of the articles. Do I have to explicitly change the build options first to have mounts working?