title: RewriteCond match for certain Query param/value pair
body: <p>I have to do a redirect to another host if a certain parameter/value pair is in the querystring. </p>
  
  <p>So far I have</p>
  
  <pre><code>RewriteCond %{REQUEST_URI}?%{QUERY_STRING} [&amp;\?]abc=23&amp;?
  RewriteRule ^(.*)$ http://anotherserver.com/$1 [R,NC,L]
  </code></pre>
  
  <p>that works for:</p>
  
  <pre><code>/index.php?id=95&amp;abc=23
  /index.php?abc=23&amp;id=95
  /index.php?id=95&amp;abc=23&amp;bla=123
  </code></pre>
  
  <p>but it also matches <code>/index.php?id=95&amp;abc=234</code> for example.</p>
  
  <p>I need a pattern that matches exactly <code>abc=23</code>, no matter where it occurs.</p>
  
  <p>Any suggestions on this? :-)</p>