Description of problem: The current packaged version is 1.2.3, however upstream are on 1.8.1 at the time of writing. 1.6.x appears to be stable here, though 1.8.x has an issue with new nokogiri versions (https://github.com/vmware/rbvmomi/issues/31).
*** Bug 1060112 has been marked as a duplicate of this bug. ***
1.8.1 is available in F21+, including the patch fixing nokogiri compatibility.