title: Regex in preg_replace to detect url format and extract elements
body: <p>I need to replace certain user-entered URLs with embedded flash objects...and I'm having trouble with a regex that I'm using to match the url...I think mainly because the URLs are SEO-friendly and therefore a bit more difficult to parse</p>
  
  <pre><code>URL structure: http://www.site.com/item/item_title_that_can_include_1('_etc-32CHARACTERALPHANUMERICGUID
  </code></pre>
  
  <p>I need to both detect a match of an URL in that format and capture the  32CHARACTERALPHANUMERICGUID which is always placed after the - in the url</p>
  
  <p>something like this:</p>
  
  <pre><code>$ret = preg_replace('#http://www\.site\.com/item/([^-])-([a-zA-Z0-9]+)#','&lt;embed&gt;itemid=$2&lt;/embed&gt;', $ret);
  </code></pre>
  
  <p>For some reason, the above does not find a match for an URL in the specified format.  I'm new to regexes, so I think I'm missing something fairly obvious. </p>