title: mod_rewrite deny access if parameter equals something
body: <p>I have urls like<br />
  mydomain.com?act=somethingbad<br />
  mydomain.com?act=somethingworse<br />
  and<br />
  mydomain.com?act=somethinggood<br />
  mydomain.com?act=somethingbetter<br /></p>
  
  <p>I need to make bad actions forbidden.
  Tried something like:</p>
  
  <pre><code>RewriteCond %{QUERY_STRING} act=(.*)
  RewriteCond %{QUERY_STRING} act=[^(somethinggood)]
  RewriteRule ^(.*) - [F]
  </code></pre>
  
  <p>Because I have more bad actions than good I want to exclude de good actions from this rule.
  But the above example doesn't work.</p>