title: installing mod_headers on Linux, apache 2.2.21
body: <p>Trying to install the mod_headers to be able to append a HTTP header with the Header directive.  But the installation process doesn't show the header module as being installed.</p>
  
  <p>Did the following steps.  Switched over to the httpd installation and under the modules/metadata directory did:</p>
  
  <pre><code> apxs -c mod_headers.c
  </code></pre>
  
  <p>the so file is created under the metadata/.libs directory (not sure why).  Added the module with:</p>
  
  <pre><code> apxs -i -a -n mod_headers ./metadata/.libs/mod_headers.so
  </code></pre>
  
  <p>Restarted apache and tried a dump of the modules but getting:</p>
  
  <pre><code> httpd: Syntax error on line 54 of /www/fkwiki/apache/conf/httpd.conf: Can't locate API module structure `mod_headers' in file /www/fkwiki/apache/modules/mod_headers.so: /www/fkwiki/apache/modules/mod_headers.so: undefined symbol: mod_headers
  </code></pre>
  
  <p>Got a warning in the installation of the module (i.e. apxs -i ....):</p>
  
  <pre><code> Warning!  dlname not found in /www/fkwiki/apache/modules/mod_headers.so
  </code></pre>
  
  <p>Anybody else have the same problem?</p>