http://www.jruby.org/2014/12/09/jruby-1-7-17
Highlights:
56 issues fixed for 1.7.17
native crypt()
Fixed bad encoding of string interpolated within backticks
popen2+ now works properly with env hash
improvements to align MRI and JRuby FFI
updated stdlib to 1.9.3p392 (+ rexml security fixes)
tzdata updated