fluent/fluent-logger-ruby — pull request #9 by kou (2013-06-14 07:16:13+00:00)
Title: Accept msgpack 0.4.7 or later

"rake spec" passes with msgpack 0.5.5 on my environment. (Debian
GNU/Linux amd64 sid) So it seems that fluent-logger can accept 0.5.x
series.