Twitter input requires proxy settings

If a Twitter input is configured:

twitter

{ type => "twitter" user => "USERNAME" password => "PASSWORD" keywords => ["something.com", "@something"] debug => true }

Logstash will fail to start with:

Input thread exception {:plugin=><LogStash::Inputs::Twitter type=>"twitter", user=>"USERNAME", keywords=>["something.com", "@something"], charset=>"UTF-8">, :exception=>#<NoMethodError: undefined method `value' for nil:NilClass>, :backtrace=>["file:/opt/logstash/logstash-1.1.12-flatjar.jar!/logstash/inputs/twitter.rb:92:in `track'", "file:/opt/logstash/logstash-1.1.12-flatjar.jar!/logstash/inputs/twitter.rb:56:in `run'", "org/jruby/RubyKernel.java:1409:in `loop'", "file:/opt/logstash/logstash-1.1.12-flatjar.jar!/logstash/inputs/twitter.rb:53:in `run'", "file:/opt/logstash/logstash-1.1.12-flatjar.jar!/logstash/agent.rb:761:in `run_input'", "file:/opt/logstash/logstash-1.1.12-flatjar.jar!/logstash/agent.rb:407:in `start_input'"], :level=>:warn}
Restarting input due to exception {:plugin=><LogStash::Inputs::Twitter type=>"twitter", user=>"USERNAME", keywords=>["something.com", "@something"], charset=>"UTF-8">, :level=>:error}

If proxy settings are initialised:

proxy_host => ""
proxy_password =>""
proxy_port => "0"
proxy_user => ""

Logstash will display errors on stderr:

Input thread exception {:plugin=><LogStash::Inputs::Twitter type=>"twitter", user=>"USERNAME", keywords=>["something.com", "@something"], charset=>"UTF-8">, :exception=>#<Errno::ECONNREFUSED: Connection refused - Connection refused>, :backtrace=>["org/jruby/ext/socket/RubyTCPSocket.java:126:in `initialize'", "org/jruby/RubyIO.java:1179:in `open'", "jar:file:/opt/logstash/logstash-1.1.12-flatjar.jar!/META-INF/jruby.home/lib/ruby/1.9/net/http.rb:762:in `connect'", "org/jruby/ext/timeout/Timeout.java:105:in `timeout'", "jar:file:/opt/logstash/logstash-1.1.12-flatjar.jar!/META-INF/jruby.home/lib/ruby/1.9/net/http.rb:762:in `connect'", "jar:file:/opt/logstash/logstash-1.1.12-flatjar.jar!/META-INF/jruby.home/lib/ruby/1.9/net/http.rb:755:in `do_start'", "jar:file:/opt/logstash/logstash-1.1.12-flatjar.jar!/META-INF/jruby.home/lib/ruby/1.9/net/http.rb:744:in `start'", "jar:file:/opt/logstash/logstash-1.1.12-flatjar.jar!/META-INF/jruby.home/lib/ruby/1.9/net/http.rb:1292:in `request'", "file:/opt/logstash/logstash-1.1.12-flatjar.jar!/logstash/inputs/twitter.rb:104:in `track'", "file:/opt/logstash/logstash-1.1.12-flatjar.jar!/logstash/inputs/twitter.rb:56:in `run'", "org/jruby/RubyKernel.java:1409:in `loop'", "file:/opt/logstash/logstash-1.1.12-flatjar.jar!/logstash/inputs/twitter.rb:53:in `run'", "file:/opt/logstash/logstash-1.1.12-flatjar.jar!/logstash/agent.rb:761:in `run_input'", "file:/opt/logstash/logstash-1.1.12-flatjar.jar!/logstash/agent.rb:407:in `start_input'"], :level=>:warn}
Restarting input due to exception {:plugin=><LogStash::Inputs::Twitter type=>"twitter", user=>"USERNAME", keywords=>["something.com", "@something"], charset=>"UTF-8">, :level=>:error}

Let me know if I missed any details.