The above didn't quite make it for me, (every attempt either gave me the dependency error or tried to fooling me yum upgrade was complete - yeah, right...sure) however this did:
rpm -e net-snmp
returned something like 'can't do it mate, since there are dependencies from net-snmp-libs-5.2.1-12.i386 and net-snmp-libs-5.2.1-12 .x86_64'
As the ruthless man I am - my answer was obvious:
rpm -e net-snmp-libs-5.2.1-12.i386
rpm -e net-snmp-libs-5.2.1-12.x86_64
rpm -e net-snmp
Followed by a swift:
yum clean all
yum upgrade
Now
rpm -q net-snmp tells me that net-snmp is not installed
I tried
yum install net-snmp
and it installed a brand new version of net-snmp (5.2.1.2-fc4.1).
I'm a happy camper!
...just lurking