title: Length of strings in unicode are different
body: <p>How come the length of the following strings is different although the number of characters in the strings are the same</p>
  
  <pre><code>echo strlen("馐 馑 馒 馓 馔 馕 首 馗 馘")."&lt;BR&gt;";
  echo strlen("Ɛ Ƒ ƒ Ɠ Ɣ ƕ Ɩ Ɨ Ƙ")."&lt;BR&gt;";
  </code></pre>
  
  <p>Outputs</p>
  
  <pre><code>35
  26
  </code></pre>