diff --git a/lib/smpp/pdu/base.rb b/lib/smpp/pdu/base.rb
index 530a4c6..c772d2d 100644
--- a/lib/smpp/pdu/base.rb
+++ b/lib/smpp/pdu/base.rb
@@ -88,7 +88,7 @@ def initialize(command_id, command_status, seq, body='')
       @command_status = command_status
       @body = body
       @sequence_number = seq
-      @data = fixed_int(length) + fixed_int(command_id) + fixed_int(command_status) + fixed_int(seq) + body   
+      @data = fixed_int(length) + fixed_int(command_id) + fixed_int(command_status) + fixed_int(seq) + body.force_encoding("ascii-8bit")
     end      
 
     def logger
diff --git a/lib/smpp/transceiver.rb b/lib/smpp/transceiver.rb
index 70516c6..4b16da6 100644
--- a/lib/smpp/transceiver.rb
+++ b/lib/smpp/transceiver.rb
@@ -31,12 +31,20 @@ def send_mt(message_id, source_addr, destination_addr, short_message, options={}
 
   # Send a concatenated message with a body of > 160 characters as multiple messages.
   def send_concat_mt(message_id, source_addr, destination_addr, message, options = {})
+    message = message.dup
     logger.debug "Sending concatenated MT: #{message}"
     if @state == :bound
       # Split the message into parts of 153 characters. (160 - 7 characters for UDH)
       parts = []
-      while message.size > 0 do
-        parts << message.slice!(0..Smpp::Transceiver.get_message_part_size(options))
+      if options[:data_coding] != 8
+        while message.size > 0 do
+          parts << message.slice!(0..Smpp::Transceiver.get_message_part_size(options))
+        end
+      else
+        bytes = message.bytes.to_a
+        0.upto(bytes.length / 134) do |part|
+          parts << bytes.slice(part * 134, 134).pack("C*")
+        end
       end
       
       0.upto(parts.size-1) do |i|
@@ -44,7 +52,8 @@ def send_concat_mt(message_id, source_addr, destination_addr, message, options =
         udh << sprintf("%c%c", 0, 3)      # This is a concatenated message 
 
         #TODO Figure out why this needs to be an int here, it's a string elsewhere
-        udh << sprintf("%c", message_id)  # The ID for the entire concatenated message
+        # so, we can use object_id because it`s always integer
+        udh << sprintf("%c", message_id.object_id & 0xFF)  # The ID for the entire concatenated message
 
         udh << sprintf("%c", parts.size)  # How many parts this message consists of
         udh << sprintf("%c", i+1)         # This is part i+1