title: Error when install php5-gd on FreeBSD 8.3(shared library "png.6" does not exist)
body: <p>I updated php to 5.3. But i cannot install gd extension(on freebsd 8.3)<br>
  The error lines:</p>
  
  <pre><code># cd /usr/ports/graphics/php5-gd/
  # make install clean
  ===&gt;   php5-gd-5.3.11 depends on file: /usr/local/bin/phpize - found
  ===&gt;   php5-gd-5.3.11 depends on file: /usr/local/bin/autoconf-2.69 - found
  ===&gt;   php5-gd-5.3.11 depends on shared library: freetype.9 - found
  ===&gt;   php5-gd-5.3.11 depends on shared library: png.6 - not found
  ===&gt;    Verifying install for png.6 in /usr/ports/graphics/png
  ===&gt;   Returning to build of php5-gd-5.3.11
  Error: shared library "png.6" does not exist
  *** Error code 1
  
  Stop in /usr/ports/graphics/php5-gd.
  *** Error code 1
  Stop in /usr/ports/graphics/php5-gd.
  </code></pre>
  
  <p>I tried update and install png lib   </p>
  
  <pre><code># cd /usr/ports/graphics/png/
  # make deinstall
  # cd make install clean
  </code></pre>
  
  <p>Then i saw:</p>
  
  <pre><code>100% tests passed, 0 tests failed out of 2
  
  Total Test time (real) =  25.96 sec
  ===&gt;  Installing for png-1.5.10
  ===&gt;   Generating temporary packing list
  ===&gt;  Checking if graphics/png already installed
  ===&gt;   png-1.5.10 is already installed
    You may wish to ``make deinstall'' and install this port again
    by ``make reinstall'' to upgrade it properly.
    If you really wish to overwrite the old port of graphics/png
    without deleting it first, set the variable "FORCE_PKG_REGISTER"
    in your environment or the "make install" command line.
  *** Error code 1
  
  Stop in /usr/ports/graphics/png.
  *** Error code 1
  Stop in /usr/ports/graphics/png.
  *** Error code 1
  Stop in /usr/ports/graphics/php5-gd.
  *** Error code 1
  Stop in /usr/ports/graphics/php5-gd.
  </code></pre>
  
  <p>If i start with directive FORCE_PKG_REGISTER - '"png.6" does not exist' apears again. I did <code>portupgrade</code> - but it did not help too. Any ideas how correctly avoid this error?</p>