0.9 is the first with Yubi support for Linux. Good luck!
I don't have access to RHEL, but 5 and 6 are pretty old, so I'm not surprised that...
Setup for 3.36 pre-release
HD Not well supported
pwsafe with Debian shows yubikey only when running as root
Find function odd behavior
Fixed in 3.35.1
Database recovery after computer crash