rubygem-treetop (1.4.10-1.el6) depends on rubygem(polyglot). But rubygem-polyglot isn't in epel and so the install fails.
Problem still opens. It's needed to build logstash.
(Better late than never...I hope) Built at http://koji.fedoraproject.org/koji/taskinfo?taskID=7839094
rubygem-polyglot-0.3.3-4.el6 has been submitted as an update for Fedora EPEL 6. https://admin.fedoraproject.org/updates/rubygem-polyglot-0.3.3-4.el6
rubygem-polyglot-0.3.3-4.el6 has been pushed to the Fedora EPEL 6 testing repository.
rubygem-polyglot-0.3.3-4.el6 has been pushed to the Fedora EPEL 6 stable repository.