diff --git a/plugins/code128.inc b/plugins/code128.inc
index 44ffc6c..22da354 100644
--- a/plugins/code128.inc
+++ b/plugins/code128.inc
@@ -107,6 +107,20 @@ function barcode_code128_barcode($barnumber, $settings) {
 
 function barcode_code128_encode($barnumber, $settings, $use_keys) {
   $enc_table=array("11011001100", "11001101100", "11001100110", "10010011000", "10010001100", "10001001100", "10011001000", "10011000100", "10001100100", "11001001000", "11001000100", "11000100100", "10110011100", "10011011100", "10011001110", "10111001100", "10011101100", "10011100110", "11001110010", "11001011100", "11001001110", "11011100100", "11001110100", "11101101110", "11101001100", "11100101100", "11100100110", "11101100100", "11100110100", "11100110010", "11011011000", "11011000110", "11000110110", "10100011000", "10001011000", "10001000110", "10110001000", "10001101000", "10001100010", "11010001000", "11000101000", "11000100010", "10110111000", "10110001110", "10001101110", "10111011000", "10111000110", "10001110110", "11101110110", "11010001110", "11000101110", "11011101000", "11011100010", "11011101110", "11101011000", "11101000110", "11100010110", "11101101000", "11101100010", "11100011010", "11101111010", "11001000010", "11110001010", "10100110000", "10100001100", "10010110000", "10010000110", "10000101100", "10000100110", "10110010000", "10110000100", "10011010000", "10011000010", "10000110100", "10000110010", "11000010010", "11001010000", "11110111010", "11000010100", "10001111010", "10100111100", "10010111100", "10010011110", "10111100100", "10011110100", "10011110010", "11110100100", "11110010100", "11110010010", "11011011110", "11011110110", "11110110110", "10101111000", "10100011110", "10001011110", "10111101000", "10111100010", "11110101000", "11110100010", "10111011110", "10111101110", "11101011110", "11110101110", "11010000100", "11010010000", "11010011100", "11000111010");
+  if ($use_keys == 'C') {
+    $enc_table=array(
+      '00' => "11011001100",
+      '01' => "11001101100",
+      '02' => "11001100110",
+      '03' => "10010011000",
+      '04' => "10010001100",
+      '05' => "10001001100",
+      '06' => "10011001000",
+      '07' => "10011000100",
+      '08' => "10001100100",
+      '09' => "11001001000",
+      '10' => "11001000100", "11000100100", "10110011100", "10011011100", "10011001110", "10111001100", "10011101100", "10011100110", "11001110010", "11001011100", "11001001110", "11011100100", "11001110100", "11101101110", "11101001100", "11100101100", "11100100110", "11101100100", "11100110100", "11100110010", "11011011000", "11011000110", "11000110110", "10100011000", "10001011000", "10001000110", "10110001000", "10001101000", "10001100010", "11010001000", "11000101000", "11000100010", "10110111000", "10110001110", "10001101110", "10111011000", "10111000110", "10001110110", "11101110110", "11010001110", "11000101110", "11011101000", "11011100010", "11011101110", "11101011000", "11101000110", "11100010110", "11101101000", "11101100010", "11100011010", "11101111010", "11001000010", "11110001010", "10100110000", "10100001100", "10010110000", "10010000110", "10000101100", "10000100110", "10110010000", "10110000100", "10011010000", "10011000010", "10000110100", "10000110010", "11000010010", "11001010000", "11110111010", "11000010100", "10001111010", "10100111100", "10010111100", "10010011110", "10111100100", "10011110100", "10011110010", "11110100100", "11110010100", "11110010010", "11011011110", "11011110110", "11110110110", "10101111000", "10100011110", "10001011110", "10111101000", "10111100010", "11110101000", "11110100010", "10111011110", "10111101110", "11101011110", "11110101110", "11010000100", "11010010000", "11010011100", "11000111010");
+  }
 
   $start = array(
     "A" => "11010000100",
@@ -118,18 +132,11 @@ function barcode_code128_encode($barnumber, $settings, $use_keys) {
   $sum = 0;
   $mfc_str = "";
   if ($use_keys == 'C') {
+    $position = 1;
     for ($i = 0; $i < strlen($barnumber); $i += 2) {
       $val = substr($barnumber, $i, 2);
-      if (is_int($val)) {
-        $sum += ($i + 1) * (int)($val);
-      }
-      elseif ($barnumber == chr(129)) {
-        $sum += ($i+1) * 100;
-      }
-      elseif ($barnumber == chr(130)) {
-        $sum += ($i + 1) * 101;
-      }
-
+      $sum += $position * (int)($val);
+      $position++;
       $mfc_str .= isset($enc_table[$val]) ? $enc_table[$val] : '';
     }
   }