diff --git a/.gitignore b/.gitignore
index 7fe46ee3..2e6d0026 100644
--- a/.gitignore
+++ b/.gitignore
@@ -15,3 +15,4 @@ profile
 spec/active_record/test.db
 .bundle
 **/.svn
+.idea
\ No newline at end of file
diff --git a/README b/README
index ff01eaa7..9d67cb58 100644
--- a/README
+++ b/README
@@ -123,21 +123,21 @@ APN on Rails has the following default configurations that you change as you see
   configatron.apn.passphrase # => ''
   configatron.apn.port # => 2195
   configatron.apn.host # => 'gateway.sandbox.push.apple.com'
-  configatron.apn.cert #=> File.join(RAILS_ROOT, 'config', 'apple_push_notification_development.pem')
+  configatron.apn.cert #=> File.join(::Rails.root, 'config', 'apple_push_notification_development.pem')
   
   # production (delivery):
   configatron.apn.host # => 'gateway.push.apple.com'
-  configatron.apn.cert #=> File.join(RAILS_ROOT, 'config', 'apple_push_notification_production.pem')
+  configatron.apn.cert #=> File.join(::Rails.root, 'config', 'apple_push_notification_production.pem')
   
   # development (feedback):
   configatron.apn.feedback.passphrase # => ''
   configatron.apn.feedback.port # => 2196
   configatron.apn.feedback.host # => 'feedback.sandbox.push.apple.com'
-  configatron.apn.feedback.cert #=> File.join(RAILS_ROOT, 'config', 'apple_push_notification_development.pem')
+  configatron.apn.feedback.cert #=> File.join(::Rails.root, 'config', 'apple_push_notification_development.pem')
   
   # production (feedback):
   configatron.apn.feedback.host # => 'feedback.push.apple.com'
-  configatron.apn.feedback.cert #=> File.join(RAILS_ROOT, 'config', 'apple_push_notification_production.pem')
+  configatron.apn.feedback.cert #=> File.join(::Rails.root, 'config', 'apple_push_notification_production.pem')
 
 That's it, now you're ready to start creating notifications.
 
diff --git a/README.textile b/README.textile
index 65d4c1b1..b02b549e 100644
--- a/README.textile
+++ b/README.textile
@@ -141,21 +141,21 @@ see fit:
   configatron.apn.passphrase # => ''
   configatron.apn.port # => 2195
   configatron.apn.host # => 'gateway.sandbox.push.apple.com'
-  configatron.apn.cert #=> File.join(RAILS_ROOT, 'config', 'apple_push_notification_development.pem')
+  configatron.apn.cert #=> File.join(::Rails.root, 'config', 'apple_push_notification_development.pem')
   
   # production (delivery):
   configatron.apn.host # => 'gateway.push.apple.com'
-  configatron.apn.cert #=> File.join(RAILS_ROOT, 'config', 'apple_push_notification_production.pem')
+  configatron.apn.cert #=> File.join(::Rails.root, 'config', 'apple_push_notification_production.pem')
   
   # development (feedback):
   configatron.apn.feedback.passphrase # => ''
   configatron.apn.feedback.port # => 2196
   configatron.apn.feedback.host # => 'feedback.sandbox.push.apple.com'
-  configatron.apn.feedback.cert #=> File.join(RAILS_ROOT, 'config', 'apple_push_notification_development.pem')
+  configatron.apn.feedback.cert #=> File.join(::Rails.root, 'config', 'apple_push_notification_development.pem')
   
   # production (feedback):
   configatron.apn.feedback.host # => 'feedback.push.apple.com'
-  configatron.apn.feedback.cert #=> File.join(RAILS_ROOT, 'config', 'apple_push_notification_production.pem')
+  configatron.apn.feedback.cert #=> File.join(::Rails.root, 'config', 'apple_push_notification_production.pem')
 </pre></code>
 
 That's it, now you're ready to start creating notifications.
diff --git a/lib/apn_on_rails/apn_on_rails.rb b/lib/apn_on_rails/apn_on_rails.rb
index 56caa6a1..1bc8bd55 100644
--- a/lib/apn_on_rails/apn_on_rails.rb
+++ b/lib/apn_on_rails/apn_on_rails.rb
@@ -3,13 +3,13 @@
 require 'configatron'
 
 rails_root = File.join(FileUtils.pwd, 'rails_root')
-if defined?(RAILS_ROOT)
-  rails_root = RAILS_ROOT
+if defined?(::Rails.root)
+  rails_root = ::Rails.root.to_s
 end
 
 rails_env = 'development'
-if defined?(RAILS_ENV)
-  rails_env = RAILS_ENV
+if defined?(::Rails.env)
+  rails_env = ::Rails.env
 end
 
 configatron.apn.set_default(:passphrase, '')
diff --git a/lib/apn_on_rails/app/models/apn/app.rb b/lib/apn_on_rails/app/models/apn/app.rb
index a0927374..60537f90 100644
--- a/lib/apn_on_rails/app/models/apn/app.rb
+++ b/lib/apn_on_rails/app/models/apn/app.rb
@@ -1,16 +1,17 @@
+# encoding: utf-8
 class APN::App < APN::Base
-  
+
   has_many :groups, :class_name => 'APN::Group', :dependent => :destroy
   has_many :devices, :class_name => 'APN::Device', :dependent => :destroy
   has_many :notifications, :through => :devices, :dependent => :destroy
   has_many :unsent_notifications, :through => :devices
   has_many :group_notifications, :through => :groups
   has_many :unsent_group_notifications, :through => :groups
-    
+
   def cert
-    (RAILS_ENV == 'production' ? apn_prod_cert : apn_dev_cert)
+    (::Rails.env.production? ? apn_prod_cert : apn_dev_cert)
   end
-  
+
   # Opens a connection to the Apple APN server and attempts to batch deliver
   # an Array of group notifications.
   # 
@@ -25,9 +26,9 @@ def send_notifications
     end
     APN::App.send_notifications_for_cert(self.cert, self.id)
   end
-  
+
   def self.send_notifications
-    apps = APN::App.all 
+    apps = APN::App.all
     apps.each do |app|
       app.send_notifications
     end
@@ -36,50 +37,56 @@ def self.send_notifications
       send_notifications_for_cert(global_cert, nil)
     end
   end
-  
+
   def self.send_notifications_for_cert(the_cert, app_id)
     # unless self.unsent_notifications.nil? || self.unsent_notifications.empty?
-      if (app_id == nil)
-        conditions = "app_id is null"
-      else 
-        conditions = ["app_id = ?", app_id]
-      end
-      begin
-        APN::Connection.open_for_delivery({:cert => the_cert}) do |conn, sock|
-          APN::Device.find_each(:conditions => conditions) do |dev|
-            dev.unsent_notifications.each do |noty|
-              conn.write(noty.message_for_sending)
-              noty.sent_at = Time.now
-              noty.save
-            end
-          end
+    if (app_id == nil)
+      conditions = "app_id is null"
+    else
+      conditions = ["app_id = ?", app_id]
+    end
+    APN::Connection.open_for_delivery({:cert => the_cert}) do |conn, sock|
+      APN::Device.find_each(:conditions => conditions) do |dev|
+        dev.unsent_notifications.each do |noty|
+          conn.write(noty.message_for_sending)
+          noty.sent_at = Time.now
+          noty.save
         end
-      rescue Exception => e
-        log_connection_exception(e)
       end
-    # end   
+    end
+    # end
   end
-  
+
   def send_group_notifications
-    if self.cert.nil? 
+    if self.cert.nil?
       raise APN::Errors::MissingCertificateError.new
       return
     end
-    unless self.unsent_group_notifications.nil? || self.unsent_group_notifications.empty? 
-      APN::Connection.open_for_delivery({:cert => self.cert}) do |conn, sock|
-        unsent_group_notifications.each do |gnoty|
-          gnoty.devices.find_each do |device|
-            conn.write(gnoty.message_for_sending(device))
+    unless self.unsent_group_notifications.nil? || self.unsent_group_notifications.empty?
+      unsent_group_notifications.each do |gnoty|
+        failed = 0
+        devices_to_send = gnoty.devices.count
+        gnoty.devices.find_in_batches(:batch_size => 100) do |devices|
+          APN::Connection.open_for_delivery({:cert => self.cert}) do |conn, sock|
+            devices.each do |device|
+              begin
+                conn.write(gnoty.message_for_sending(device))
+              rescue Exception => e
+                puts e.message
+                failed += 1
+              end
+            end
           end
-          gnoty.sent_at = Time.now
-          gnoty.save
         end
+        puts "Sent to: #{devices_to_send - failed}/#{devices_to_send} "
+        gnoty.sent_at = Time.now
+        gnoty.save
       end
     end
   end
-  
+
   def send_group_notification(gnoty)
-    if self.cert.nil? 
+    if self.cert.nil?
       raise APN::Errors::MissingCertificateError.new
       return
     end
@@ -93,14 +100,14 @@ def send_group_notification(gnoty)
       end
     end
   end
-  
+
   def self.send_group_notifications
     apps = APN::App.all
     apps.each do |app|
       app.send_group_notifications
     end
-  end          
-  
+  end
+
   # Retrieves a list of APN::Device instnces from Apple using
   # the <tt>devices</tt> method. It then checks to see if the
   # <tt>last_registered_at</tt> date of each APN::Device is
@@ -117,8 +124,10 @@ def process_devices
       return
     end
     APN::App.process_devices_for_cert(self.cert)
-  end # process_devices
-  
+  end
+
+  # process_devices
+
   def self.process_devices
     apps = APN::App.all
     apps.each do |app|
@@ -129,23 +138,23 @@ def self.process_devices
       APN::App.process_devices_for_cert(global_cert)
     end
   end
-  
+
   def self.process_devices_for_cert(the_cert)
     puts "in APN::App.process_devices_for_cert"
     APN::Feedback.devices(the_cert).each do |device|
       if device.last_registered_at < device.feedback_at
         puts "device #{device.id} -> #{device.last_registered_at} < #{device.feedback_at}"
         device.destroy
-      else 
+      else
         puts "device #{device.id} -> #{device.last_registered_at} not < #{device.feedback_at}"
       end
-    end 
+    end
   end
-  
-  
+
+
   protected
   def log_connection_exception(ex)
     puts ex.message
   end
-    
+
 end
\ No newline at end of file
diff --git a/lib/apn_on_rails/app/models/apn/base.rb b/lib/apn_on_rails/app/models/apn/base.rb
index c54fdc51..290537ff 100644
--- a/lib/apn_on_rails/app/models/apn/base.rb
+++ b/lib/apn_on_rails/app/models/apn/base.rb
@@ -1,6 +1,8 @@
 module APN
   class Base < ActiveRecord::Base # :nodoc:
     
+    self.abstract_class = true
+    
     def self.table_name # :nodoc:
       self.to_s.gsub("::", "_").tableize
     end
diff --git a/lib/apn_on_rails/app/models/apn/device.rb b/lib/apn_on_rails/app/models/apn/device.rb
index 1864ca0a..3e94461f 100644
--- a/lib/apn_on_rails/app/models/apn/device.rb
+++ b/lib/apn_on_rails/app/models/apn/device.rb
@@ -15,7 +15,7 @@ class APN::Device < APN::Base
   has_many :unsent_notifications, :class_name => 'APN::Notification', :conditions => 'sent_at is null'
   
   validates_uniqueness_of :token, :scope => :app_id
-  validates_format_of :token, :with => /^[a-z0-9]{8}\s[a-z0-9]{8}\s[a-z0-9]{8}\s[a-z0-9]{8}\s[a-z0-9]{8}\s[a-z0-9]{8}\s[a-z0-9]{8}\s[a-z0-9]{8}$/
+  #validates_format_of :token, :with => /^[a-z0-9]{8}\s[a-z0-9]{8}\s[a-z0-9]{8}\s[a-z0-9]{8}\s[a-z0-9]{8}\s[a-z0-9]{8}\s[a-z0-9]{8}\s[a-z0-9]{8}$/
   
   before_create :set_last_registered_at
   
diff --git a/lib/apn_on_rails/app/models/apn/group_notification.rb b/lib/apn_on_rails/app/models/apn/group_notification.rb
index fb7f8e8f..19679877 100644
--- a/lib/apn_on_rails/app/models/apn/group_notification.rb
+++ b/lib/apn_on_rails/app/models/apn/group_notification.rb
@@ -1,18 +1,19 @@
+# encoding: utf-8
 class APN::GroupNotification < APN::Base
   include ::ActionView::Helpers::TextHelper
   extend ::ActionView::Helpers::TextHelper
   serialize :custom_properties
-  
+
   belongs_to :group, :class_name => 'APN::Group'
-  has_one    :app, :class_name => 'APN::App', :through => :group
-  has_many   :device_groupings, :through => :group
-  
+  has_one :app, :class_name => 'APN::App', :through => :group
+  has_many :device_groupings, :through => :group
+
   validates_presence_of :group_id
-  
+
   def devices
     self.group.devices
   end
-  
+
   # Stores the text alert message you want to send to the device.
   # 
   # If the message is over 150 characters long it will get truncated
@@ -23,7 +24,7 @@ def alert=(message)
     end
     write_attribute('alert', message)
   end
-  
+
   # Creates a Hash that will be the payload of an APN.
   # 
   # Example:
@@ -45,17 +46,25 @@ def apple_hash
     result['aps']['alert'] = self.alert if self.alert
     result['aps']['badge'] = self.badge.to_i if self.badge
     if self.sound
-      result['aps']['sound'] = self.sound if self.sound.is_a? String
+      result['aps']['sound'] = self.sound if self.sound.is_a?(String) && self.sound.strip.present?
       result['aps']['sound'] = "1.aiff" if self.sound.is_a?(TrueClass)
     end
     if self.custom_properties
-      self.custom_properties.each do |key,value|
+      self.custom_properties.each do |key, value|
         result["#{key}"] = "#{value}"
       end
     end
     result
   end
-  
+
+  def payload
+    multi_json_dump(apple_hash)
+  end
+
+  def payload_size
+    payload.bytesize
+  end
+
   # Creates the JSON string required for an APN message.
   # 
   # Example:
@@ -67,13 +76,37 @@ def apple_hash
   def to_apple_json
     self.apple_hash.to_json
   end
-  
+
   # Creates the binary message needed to send to Apple.
+  #def message_for_sending(device)
+  #  json = self.to_apple_json.gsub(/\\u([0-9a-z]{4})/) { |s| [$1.to_i(16)].pack("U") } # This will create non encoded string. Otherwise the string is encoded from utf8 to ascii with unicode representation (i.e. \\u05d2)
+  #  message = "\0\0 #{device.to_hexa}\0".force_encoding("UTF-8") + "#{json.length.chr}#{json}".force_encoding("UTF-8")
+  #  raise APN::Errors::ExceededMessageSizeError.new(message) if message.size.to_i > 256
+  #  message
+  #end
+
+  # This method conforms to the enhanced binary format.
+  # http://developer.apple.com/library/ios/#documentation/NetworkingInternet/Conceptual/RemoteNotificationsPG/CommunicatingWIthAPS/CommunicatingWIthAPS.html#//apple_ref/doc/uid/TP40008194-CH101-SW4
   def message_for_sending(device)
-    json = self.to_apple_json
-    message = "\0\0 #{device.to_hexa}\0#{json.length.chr}#{json}"
+    message = [1, device.id, 1.day.to_i, 0, 32, device.token, payload_size, payload].pack("cNNccH*na*")
     raise APN::Errors::ExceededMessageSizeError.new(message) if message.size.to_i > 256
     message
   end
-  
+
+
+  private
+
+  def multi_json_load(string, options = {})
+    # Calling load on multi_json less than v1.3.0 attempts to load a file from disk. Check the version explicitly.
+    if Gem.loaded_specs['multi_json'].version >= Gem::Version.create('1.3.0')
+      MultiJson.load(string, options)
+    else
+      MultiJson.decode(string, options)
+    end
+  end
+
+  def multi_json_dump(string, options = {})
+    MultiJson.respond_to?(:dump) ? MultiJson.dump(string, options) : MultiJson.encode(string, options)
+  end
+
 end # APN::Notification
\ No newline at end of file
diff --git a/lib/apn_on_rails/app/models/apn/notification.rb b/lib/apn_on_rails/app/models/apn/notification.rb
index 068f13a8..473d055b 100644
--- a/lib/apn_on_rails/app/models/apn/notification.rb
+++ b/lib/apn_on_rails/app/models/apn/notification.rb
@@ -54,7 +54,7 @@ def apple_hash
     result['aps']['alert'] = self.alert if self.alert
     result['aps']['badge'] = self.badge.to_i if self.badge
     if self.sound
-      result['aps']['sound'] = self.sound if self.sound.is_a? String
+      result['aps']['sound'] = self.sound if self.sound.is_a?(String) && self.sound.strip.present?
       result['aps']['sound'] = "1.aiff" if self.sound.is_a?(TrueClass)
     end
     if self.custom_properties
@@ -79,7 +79,7 @@ def to_apple_json
   
   # Creates the binary message needed to send to Apple.
   def message_for_sending
-    json = self.to_apple_json
+    json = self.to_apple_json.gsub(/\\u([0-9a-z]{4})/) {|s| [$1.to_i(16)].pack("U")} # This will create non encoded string. Otherwise the string is encoded from utf8 to ascii with unicode representation (i.e. \\u05d2)
     message = "\0\0 #{self.device.to_hexa}\0#{json.length.chr}#{json}"
     raise APN::Errors::ExceededMessageSizeError.new(message) if message.size.to_i > 256
     message
diff --git a/lib/apn_on_rails/libs/connection.rb b/lib/apn_on_rails/libs/connection.rb
index c44f8a7e..ef06de77 100644
--- a/lib/apn_on_rails/libs/connection.rb
+++ b/lib/apn_on_rails/libs/connection.rb
@@ -1,3 +1,4 @@
+# encoding: utf-8
 module APN
   module Connection
     
@@ -59,7 +60,7 @@ def open(options = {}, &block) # :nodoc:
         ssl.connect
   
         yield ssl, sock if block_given?
-  
+      ensure
         ssl.close
         sock.close
       end
diff --git a/lib/apn_on_rails/libs/feedback.rb b/lib/apn_on_rails/libs/feedback.rb
index 258ed22e..86f64c2f 100644
--- a/lib/apn_on_rails/libs/feedback.rb
+++ b/lib/apn_on_rails/libs/feedback.rb
@@ -13,10 +13,10 @@ class << self
       def devices(cert, &block)
         devices = []
         return if cert.nil? 
-        APN::Connection.open_for_feedback({:cert => cert}) do |conn, sock|          
+        APN::Connection.open_for_feedback({:cert => cert}) do |conn, sock|
           while line = conn.read(38)   # Read 38 bytes from the SSL socket
-            feedback = line.unpack('N1n1H140')            
-            token = feedback[2].scan(/.{0,8}/).join(' ').strip
+            feedback = line.unpack('N1n1H140')
+            token = feedback[2].strip
             device = APN::Device.find(:first, :conditions => {:token => token})
             if device
               device.feedback_at = Time.at(feedback[0])
@@ -25,7 +25,7 @@ def devices(cert, &block)
           end
         end
         devices.each(&block) if block_given?
-        return devices
+        devices
       end # devices
       
       def process_devices