Estoy tratando de usar el 'twitter' de ruby ​​gem, pero por razones desconocidas no puedo hacerlo funcionar.

Aquí está el código .rb:

require 'twitter'

puts "Greetings, World!"
puts "Checkpoint 1"
Twitter.configure do |config|
  config.consumer_key = "xxxxxxx" #removed for posting
  config.consumer_secret = "xxxxxxx" #removed for posting
  config.oauth_token = "xxxxxxx" #removed for posting
  config.oauth_token_secret = "xxxxxxx" #removed for posting
end
Twitter.verify_credentials
puts "Checkpoint 2"

y me sale el siguiente error:

Greetings, World!
Checkpoint 1
C:/Ruby200-x64/lib/ruby/2.0.0/net/http.rb:918:in `connect': SSL_connect returned=1 errno=0 state=SSLv3 read server certificate B: certificate verify failed (Twitter::Error::ClientError)
from C:/Ruby200-x64/lib/ruby/2.0.0/net/http.rb:918:in `block in connect'
from C:/Ruby200-x64/lib/ruby/2.0.0/timeout.rb:66:in `timeout'
from C:/Ruby200-x64/lib/ruby/2.0.0/net/http.rb:918:in `connect'
from C:/Ruby200-x64/lib/ruby/2.0.0/net/http.rb:862:in `do_start'
from C:/Ruby200-x64/lib/ruby/2.0.0/net/http.rb:851:in `start'
from C:/Ruby200-x64/lib/ruby/2.0.0/net/http.rb:1367:in `request'
from C:/Ruby200-x64/lib/ruby/2.0.0/net/http.rb:1126:in `get'
from C:/Ruby200-x64/lib/ruby/gems/2.0.0/gems/faraday-0.8.7/lib/faraday/adapter/net_http.rb:73:in `perform_request'
from C:/Ruby200-x64/lib/ruby/gems/2.0.0/gems/faraday-0.8.7/lib/faraday/adapter/net_http.rb:38:in `call'
from C:/Ruby200-x64/lib/ruby/gems/2.0.0/gems/faraday-0.8.7/lib/faraday/response.rb:8:in `call'
from C:/Ruby200-x64/lib/ruby/gems/2.0.0/gems/faraday-0.8.7/lib/faraday/response.rb:8:in `call'
from C:/Ruby200-x64/lib/ruby/gems/2.0.0/gems/faraday-0.8.7/lib/faraday/response.rb:8:in `call'
from C:/Ruby200-x64/lib/ruby/gems/2.0.0/gems/faraday-0.8.7/lib/faraday/request/url_encoded.rb:14:in `call'
from C:/Ruby200-x64/lib/ruby/gems/2.0.0/gems/faraday-0.8.7/lib/faraday/request/multipart.rb:13:in `call'
from C:/Ruby200-x64/lib/ruby/gems/2.0.0/gems/twitter-4.8.0/lib/twitter/request/multipart_with_file.rb:14:in `call'
from C:/Ruby200-x64/lib/ruby/gems/2.0.0/gems/faraday-0.8.7/lib/faraday/connection.rb:247:in `run_request'
from C:/Ruby200-x64/lib/ruby/gems/2.0.0/gems/faraday-0.8.7/lib/faraday/connection.rb:100:in `get'
from C:/Ruby200-x64/lib/ruby/gems/2.0.0/gems/twitter-4.8.0/lib/twitter/client.rb:108:in `request'
from C:/Ruby200-x64/lib/ruby/gems/2.0.0/gems/twitter-4.8.0/lib/twitter/client.rb:66:in `get'        
from C:/Ruby200-x64/lib/ruby/gems/2.0.0/gems/twitter-4.8.0/lib/twitter/api/utils.rb:82:in `object_from_response'
from C:/Ruby200-x64/lib/ruby/gems/2.0.0/gems/twitter-4.8.0/lib/twitter/api/users.rb:50:in `verify_credentials'
from C:/Ruby200-x64/lib/ruby/gems/2.0.0/gems/twitter-4.8.0/lib/twitter.rb:60:in `method_missing'
from C:/Ruby200-x64/AppCode/twitter_connect.rb:13:in `<main>'

Soy un novato Ruby y no puedo entender el error del cliente ... tal vez me esté perdiendo algo. También he confirmado que mis credenciales de Oauth están funcionando en python.

Gracias de antemano y espero su ayuda.