diff --git a/lib/biju/modem.rb b/lib/biju/modem.rb
index 8312688..8d54b46 100644
--- a/lib/biju/modem.rb
+++ b/lib/biju/modem.rb
@@ -26,7 +26,10 @@ module Biju
       wait(length: 0, timeout: 0)
     end
 
-    def wait(length: 0, timeout: 10)
+    def wait(options = {})
+      length = options[:length] || 0
+      timeout = options[:timeout] || 10
+
       buffer = ''
       Timeout.timeout(timeout) do
         while IO.select([connection], [], [], 0.25) || buffer.length < length
diff --git a/lib/biju/pdu.rb b/lib/biju/pdu.rb
index d6a7ba3..56d63e3 100644
--- a/lib/biju/pdu.rb
+++ b/lib/biju/pdu.rb
@@ -11,7 +11,9 @@ require 'biju/pdu/type_of_address'
 
 module Biju
   module PDU
-    def self.encode(phone_number, message, type_of_address: :international)
+    def self.encode(phone_number, message, options = {})
+      type_of_address = options[:type_of_address] || :international
+
       phone_number = PhoneNumber.encode(phone_number)
       user_data = UserData.encode(message)
       first_octet = FirstOctet.new.message_type_indicator!(:sms_submit)
diff --git a/lib/biju/pdu/encoding/gsm7bit.rb b/lib/biju/pdu/encoding/gsm7bit.rb
index 242c612..7a3543a 100644
--- a/lib/biju/pdu/encoding/gsm7bit.rb
+++ b/lib/biju/pdu/encoding/gsm7bit.rb
@@ -1,3 +1,5 @@
+# encoding: UTF-8
+
 module Biju
   module PDU
     module Encoding
@@ -28,7 +30,9 @@ module Biju
           0x65 => '€',
         }
 
-        def self.decode(string, length: 0)
+        def self.decode(string, options = {})
+          length = options[:length] || 0
+
           res = ''
           next_char = 0
           current_length = 0
@@ -98,7 +102,9 @@ module Biju
           end
         end
 
-        def self.get_septet(char, escape: false)
+        def self.get_septet(char, options = {})
+          escape = options[:escape] || false
+
           char = (!escape ? BASIC_7BIT_CHARACTER_SET.index(char) : BASIC_7BIT_CHARACTER_SET_EXTENSION.key(char))
 
           return nil unless char
diff --git a/lib/biju/pdu/encoding/ucs2.rb b/lib/biju/pdu/encoding/ucs2.rb
index a5360f6..04cd4a5 100644
--- a/lib/biju/pdu/encoding/ucs2.rb
+++ b/lib/biju/pdu/encoding/ucs2.rb
@@ -2,7 +2,9 @@ module Biju
   module PDU
     module Encoding
       class UCS2
-        def self.decode(string, length: 0)
+        def self.decode(string, options = {})
+          length = options[:length] || 0
+
           string.scan(/.{4}/).map { |char| char.hex.chr('UCS-2BE') }.join
           .encode('UTF-8', 'UCS-2BE')
         end
diff --git a/lib/biju/pdu/phone_number.rb b/lib/biju/pdu/phone_number.rb
index 4794af6..40e4279 100644
--- a/lib/biju/pdu/phone_number.rb
+++ b/lib/biju/pdu/phone_number.rb
@@ -3,7 +3,9 @@ module Biju
     class PhoneNumber
       attr_accessor :type_of_address, :number
 
-      def self.encode(number, type_of_address: :international)
+      def self.encode(number, options = {})
+        type_of_address = options[:type_of_address] || :international
+
         number = number + 'F' if number.length.odd?
         new(
           number.scan(/../).map(&:reverse).join,
@@ -11,7 +13,9 @@ module Biju
         )
       end
 
-      def initialize(number, type_of_address: :international)
+      def initialize(number, options = {})
+        type_of_address = options[:type_of_address] || :international
+
         self.number = number
         self.type_of_address = TypeOfAddress.new(type_of_address)
       end
diff --git a/lib/biju/pdu/user_data.rb b/lib/biju/pdu/user_data.rb
index 0614eb2..c143751 100644
--- a/lib/biju/pdu/user_data.rb
+++ b/lib/biju/pdu/user_data.rb
@@ -6,10 +6,10 @@ module Biju
         ucs2: Encoding::UCS2,
       }
 
-      attr_accessor :encoding, :message, :length
+      attr_accessor :encoding, :message, :length, :user_data_header
 
-      def self.encode(message, encoding: nil)
-        encoding = DataCodingScheme.autodetect(message) if encoding.nil?
+      def self.encode(message, options = {})
+        encoding = options[:encoding] || DataCodingScheme.autodetect(message)
 
         raise ArgumentError, 'Unknown encoding' unless ENCODING.has_key?(encoding)
         res = ENCODING[encoding].encode(message)
@@ -17,10 +17,13 @@ module Biju
         new(message: res[0], length: res[1][:length], encoding: encoding)
       end
 
-      def initialize(message: '', length: 0, encoding: :gsm7bit)
-        self.encoding = DataCodingScheme.new(encoding)
-        self.message = message
-        self.length = length
+      def initialize(options = {})
+        self.encoding = DataCodingScheme.new(options[:encoding] || :gsm7bit)
+        self.message = options[:message] || ''
+
+        self.length = options[:length] || 0
+
+        self.user_data_header = options[:user_data_header] || false
       end
 
       def decode
diff --git a/spec/biju/pdu/data_coding_scheme_spec.rb b/spec/biju/pdu/data_coding_scheme_spec.rb
index 184a23a..b482dfa 100644
--- a/spec/biju/pdu/data_coding_scheme_spec.rb
+++ b/spec/biju/pdu/data_coding_scheme_spec.rb
@@ -1,3 +1,4 @@
+# encoding: UTF-8
 require 'spec_helper'
 require 'biju/pdu'
 
diff --git a/spec/biju/pdu/encoding/gsm7bit_spec.rb b/spec/biju/pdu/encoding/gsm7bit_spec.rb
index f2ffed6..dd470ac 100644
--- a/spec/biju/pdu/encoding/gsm7bit_spec.rb
+++ b/spec/biju/pdu/encoding/gsm7bit_spec.rb
@@ -1,3 +1,4 @@
+# encoding: UTF-8
 require 'spec_helper'
 require 'biju/pdu/encoding/gsm7bit'
 
diff --git a/spec/biju/pdu/encoding/ucs2_spec.rb b/spec/biju/pdu/encoding/ucs2_spec.rb
index dfe50c2..dd6dec3 100644
--- a/spec/biju/pdu/encoding/ucs2_spec.rb
+++ b/spec/biju/pdu/encoding/ucs2_spec.rb
@@ -1,3 +1,4 @@
+# encoding: UTF-8
 require 'spec_helper'
 require 'biju/pdu/encoding/ucs2'