title: String Manipulation with case sensitivity
body: <p>Lets say we have a variable like;</p>
  
  <pre><code>set test=This is a Test string.
  </code></pre>
  
  <p>and we want to replace every lower-case <code>t</code> with upper-case <code>X</code> so desired output;</p>
  
  <pre><code>This is a TesX sXring.
  </code></pre>
  
  <p>i tryed using string manipulation <code>set test=%test:t=X%</code> but its replacing every <code>t</code> with <code>X</code>. I also tryed <a href="http://www.dostips.com/forum/viewtopic.php?f=3&amp;t=6044" rel="nofollow">JREPL.bat</a> from @dbenham but cant work it out.</p>