diff --git a/.travis.yml b/.travis.yml
index 8193a1496..cf1d21424 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -1,14 +1,18 @@
 language: ruby
 bundler_args: --without development
 script: "bundle exec rake \"parallel:spec[1]\""
 notifications:
   email: false
 rvm:
   - 2.1.0
   - 2.0.0
   - 1.9.3
   - 1.8.7
   - ruby-head
+  - jruby-19mode
 matrix:
   allow_failures:
     - rvm: ruby-head
+    - rvm: jruby-19mode
+env:
+  - JRUBY_OPTS="-J-Xmx1024m"
diff --git a/Gemfile b/Gemfile
index 7188ad9b7..5e17080d7 100644
--- a/Gemfile
+++ b/Gemfile
@@ -1,88 +1,92 @@
 source ENV['GEM_SOURCE'] || "https://rubygems.org"
 
 def location_for(place, fake_version = nil)
   if place =~ /^(git[:@][^#]*)#(.*)/
     [fake_version, { :git => $1, :branch => $2, :require => false }].compact
   elsif place =~ /^file:\/\/(.*)/
     ['>= 0', { :path => File.expand_path($1), :require => false }]
   else
     [place, { :require => false }]
   end
 end
 
 # C Ruby (MRI) or Rubinius, but NOT Windows
 platforms :ruby do
   gem 'pry', :group => :development
   gem 'yard', :group => :development
   gem 'redcarpet', '~> 2.0', :group => :development
   gem "racc", "1.4.9", :group => :development
 end
 
 gem "puppet", :path => File.dirname(__FILE__), :require => false
 gem "facter", *location_for(ENV['FACTER_LOCATION'] || ['> 1.6', '< 3'])
 gem "hiera", *location_for(ENV['HIERA_LOCATION'] || '~> 1.0')
 gem "rake", :require => false
 gem "rgen", "0.6.5", :require => false
 
 
 group(:development, :test) do
 
   # Jenkins workers may be using RSpec 2.9, so RSpec 2.11 syntax
   # (like `expect(value).to eq matcher`) should be avoided.
   gem "rspec", "~> 2.11.0", :require => false
 
   # Mocha is not compatible across minor version changes; because of this only
   # versions matching ~> 0.10.5 are supported. All other versions are unsupported
   # and can be expected to fail.
   gem "mocha", "~> 0.10.5", :require => false
 
   gem "yarjuf", "~> 1.0"
 
-  # json-schema does not support windows, so use the 'ruby' platform to exclude it on windows
-  platforms :ruby do
-    # json-schema uses multi_json, but chokes with multi_json 1.7.9, so prefer 1.7.7
-    gem "multi_json", "1.7.7", :require => false
-    gem "json-schema", "2.1.1", :require => false
-  end
+  # json-schema does not support windows, so omit it from the platforms list
+  # json-schema uses multi_json, but chokes with multi_json 1.7.9, so prefer 1.7.7
+  gem "multi_json", "1.7.7", :require => false, :platforms => [:ruby, :jruby]
+  gem "json-schema", "2.1.1", :require => false, :platforms => [:ruby, :jruby]
 end
 
 group(:development) do
   case RUBY_VERSION
   when /^1.8/
     gem 'ruby-prof', "~> 0.13.1", :require => false
   else
     gem 'ruby-prof', :require => false
   end
 end
 
 group(:extra) do
   gem "rack", "~> 1.4", :require => false
   gem "activerecord", '~> 3.2', :require => false
   gem "couchrest", '~> 1.0', :require => false
   gem "net-ssh", '~> 2.1', :require => false
   gem "puppetlabs_spec_helper", :require => false
-  gem "sqlite3", :require => false
   gem "stomp", :require => false
   gem "tzinfo", :require => false
-  gem "msgpack", :require => false
+  case RUBY_PLATFORM
+  when 'java'
+    gem "jdbc-sqlite3", :require => false
+    gem "msgpack-jruby", :require => false
+  else
+    gem "sqlite3", :require => false
+    gem "msgpack", :require => false
+  end
 end
 
 require 'yaml'
 data = YAML.load_file(File.join(File.dirname(__FILE__), 'ext', 'project_data.yaml'))
 bundle_platforms = data['bundle_platforms']
 data['gem_platform_dependencies'].each_pair do |gem_platform, info|
   if bundle_deps = info['gem_runtime_dependencies']
     bundle_platform = bundle_platforms[gem_platform] or raise "Missing bundle_platform"
     platform(bundle_platform.intern) do
       bundle_deps.each_pair do |name, version|
         gem(name, version, :require => false)
       end
     end
   end
 end
 
 if File.exists? "#{__FILE__}.local"
   eval(File.read("#{__FILE__}.local"), binding)
 end
 
 # vim:filetype=ruby
diff --git a/lib/puppet/agent.rb b/lib/puppet/agent.rb
index 72be5c18d..a06f2e771 100644
--- a/lib/puppet/agent.rb
+++ b/lib/puppet/agent.rb
@@ -1,122 +1,122 @@
 require 'puppet/application'
 
 # A general class for triggering a run of another
 # class.
 class Puppet::Agent
   require 'puppet/agent/locker'
   include Puppet::Agent::Locker
 
   require 'puppet/agent/disabler'
   include Puppet::Agent::Disabler
 
   attr_reader :client_class, :client, :splayed, :should_fork
 
   # Just so we can specify that we are "the" instance.
   def initialize(client_class, should_fork=true)
     @splayed = false
 
     @should_fork = can_fork? && should_fork
     @client_class = client_class
   end
 
   def can_fork?
-    Puppet.features.posix?
+    Puppet.features.posix? && RUBY_PLATFORM != 'java'
   end
 
   def needing_restart?
     Puppet::Application.restart_requested?
   end
 
   # Perform a run with our client.
   def run(client_options = {})
     if running?
       Puppet.notice "Run of #{client_class} already in progress; skipping  (#{lockfile_path} exists)"
       return
     end
     if disabled?
       Puppet.notice "Skipping run of #{client_class}; administratively disabled (Reason: '#{disable_message}');\nUse 'puppet agent --enable' to re-enable."
       return
     end
 
     result = nil
     block_run = Puppet::Application.controlled_run do
       splay client_options.fetch :splay, Puppet[:splay]
       result = run_in_fork(should_fork) do
         with_client do |client|
           begin
             client_args = client_options.merge(:pluginsync => Puppet[:pluginsync])
             lock { client.run(client_args) }
           rescue SystemExit,NoMemoryError
             raise
           rescue Exception => detail
             Puppet.log_exception(detail, "Could not run #{client_class}: #{detail}")
           end
         end
       end
       true
     end
     Puppet.notice "Shutdown/restart in progress (#{Puppet::Application.run_status.inspect}); skipping run" unless block_run
     result
   end
 
   def stopping?
     Puppet::Application.stop_requested?
   end
 
   # Have we splayed already?
   def splayed?
     splayed
   end
 
   # Sleep when splay is enabled; else just return.
   def splay(do_splay = Puppet[:splay])
     return unless do_splay
     return if splayed?
 
     time = rand(Puppet[:splaylimit] + 1)
     Puppet.info "Sleeping for #{time} seconds (splay is enabled)"
     sleep(time)
     @splayed = true
   end
 
   def run_in_fork(forking = true)
     return yield unless forking or Puppet.features.windows?
 
     child_pid = Kernel.fork do
       $0 = "puppet agent: applying configuration"
       begin
         exit(yield)
       rescue SystemExit
         exit(-1)
       rescue NoMemoryError
         exit(-2)
       end
     end
     exit_code = Process.waitpid2(child_pid)
     case exit_code[1].exitstatus
     when -1
       raise SystemExit
     when -2
       raise NoMemoryError
     end
     exit_code[1].exitstatus
   end
 
   private
 
   # Create and yield a client instance, keeping a reference
   # to it during the yield.
   def with_client
     begin
       @client = client_class.new
     rescue SystemExit,NoMemoryError
       raise
     rescue Exception => detail
       Puppet.log_exception(detail, "Could not create instance of #{client_class}: #{detail}")
       return
     end
     yield @client
   ensure
     @client = nil
   end
 end