Otherwise you may get confusing errors. E.g. see https://bugzilla.redhat.com/show_bug.cgi?id=451009
https://engineering.redhat.com/docbot/en-US/Red_Hat_Enterprise_MRG/1.0/html/MRG_Release_Notes/sect-MRG_Release_Notes-Known_Issues-RHM_Known_Issues.html