Redhat 7.3 is 11 years old! (7.3 (Valhalla), May 6, 2002 (Linux 2.4.18-3)
All the packages are from that era and it is more then possible that rpm's import options wasn't present (or present in a different form). I've tried to find when --import was introduced, but the rpm release page
only goes back as far as 2007.
Many, many things have changed over the last 11 years. I would strongly suggest you start using a modern, up-to-date distro.
EDIT: Too slow, again....