--- pathologic.module	Tue Mar 20 04:26:38 2012
+++ pathologic.module	Wed Mar 21 09:45:14 2012
@@ -190,69 +190,76 @@
     return $matches[0];
   }
 
-  // First, "files:" support. This is fairly easy.
+  // We have a local path. We now have to transform this into a valid URL.
+  // How to do this depends on whether it is a path handled by Drupal (e.g.
+  // node/21) or a path to an existing resource (e.g.
+  // sites/default/files/my-image.jpg). Paths with a valid (file) scheme are
+  // handled first. For now only the files: scheme is handled.
+  $url = FALSE;
   if (isset($parts['scheme']) && $parts['scheme'] === 'files') {
-    // Can we create a file URL for it?
-    $file_url = file_create_url(file_build_uri($parts['path']));
-    if ($file_url) {
-      return $matches[1] . '="' . $file_url;
+    // Create the URL for it.
+    $url = file_create_url(file_build_uri($parts['path']));
+  }
+  else {
+    // No scheme or a scheme that will be ignored (http, https, internal) was
+    // used. Check if the path is an existing resource or not? But be aware of
+    // the query parameter q (probably in combination with index.php as path,
+    // but Drupal will also work with default.php?q=... if so configured).
+    if (isset($parts['query'])) {
+      parse_str($parts['query'], $parts['qparts']);
+      if (isset($parts['qparts']['q'])) {
+        $parts['path'] = $parts['qparts']['q'];
+        unset($parts['qparts']['q']);
+      }
     }
     else {
-      // That didn't work. Bail out.
+      $parts['qparts'] = NULL;
+    }
+
+    // If we don't have a path yet, bail out.
+    if (!isset($parts['path'])) {
       return $matches[0];
     }
-  }
-  elseif (file_exists(realpath($parts['path']))) {
-    // Okay, they didn't use files:, but does it appear that the path is still
-    // to a real file on the disk? If so, we don't want to adjust for language.
-    // Also, skip all other tweaks.
-    $settings['langcode'] = LANGUAGE_NONE;
-  }
+    // Chop off any starting slash (i.e if we had something like ?q=/...).
+    if (strpos($parts['path'], '/') === 0) {
+      $parts['path'] = substr($parts['path'], 1);
+    }
 
-  // Examine the query part of the URL. Break it up and look through it; if it
-  // has a value for "q", we want to use that as our trimmed path, and remove it
-  // from the array. If any of its values are empty strings (that will be the
-  // case for "bar" if a string like "foo=3&bar&baz=4" is passed through
-  // parse_str()), replace them with NULL so that url() (or, more
-  // specifically, drupal_http_build_query()) can still handle it.
-  if (isset($parts['query'])) {
-    parse_str($parts['query'], $parts['qparts']);
-    foreach ($parts['qparts'] as $key => $value) {
-      if ($value === '') {
-        $parts['qparts'][$key] = NULL;
+    if (file_exists(realpath($parts['path']))) {
+      // Note: this will loose any query and fragment part.
+      $url = file_create_url($parts['path']);
+      // So we are adding that back, if necessary.
+      if (isset($parts['qparts'])) {
+        $url .= '?' . drupal_http_build_query($parts['qparts']);
       }
-      elseif ($key === 'q') {
-        $parts['path'] = $value;
-        unset($parts['qparts']['q']);
+      if (isset($parts['fragment']) && $parts['fragment'] !== '') {
+        $url .= '#' . $parts['fragment'];
       }
     }
+    else {
+      // Assemble the URL options to pass with the path.
+      // Start with the absolute setting.
+      $url_options = array(
+        'absolute' => $settings['current_settings']['absolute'],
+      );
+      // Add query part if not empty.
+      if (!empty($parts['qparts'])) {
+        $url_options['query'] = $parts['qparts'];
+      }
+      // Add fragment part if not empty.
+      if (!empty($parts['fragment'])) {
+        $url_options['fragment'] = $parts['fragment'];
+      }
+      // Add language of current context as Drupal may rewrite URL's based on
+      // language.
+      if (!empty($settings['langcode']) && $settings['langcode'] !== LANGUAGE_NONE) {
+        if (isset($settings['language_list'][$settings['langcode']])) {
+          $url_options['language'] = isset($settings['language_list'][$settings['langcode']]);
+        }
+      }
+      $url = url($parts['path'], $url_options);
+    }
   }
-  else {
-    $parts['qparts'] = NULL;
-  }
-
-  // If we don't have a path yet, bail out.
-  if (!isset($parts['path'])) {
-    return $matches[0];
-  }
-
-  // Okay, format the URL.
-  // If there's still a slash lingering at the start of the path, chop it off.
-  // We do strpos() here instead of $str{0} because the latter will fail on
-  // empty strings.
-  if (strpos($parts['path'], '/') === 0) {
-    $parts['path'] = substr($parts['path'], 1);
-  }
-
-  $url = url(
-    $parts['path'] === '' ? '<front>' : $parts['path'],
-    array(
-      'query' => $parts['qparts'],
-      'fragment' => isset($parts['fragment']) ? $parts['fragment'] : NULL,
-      'absolute' => $settings['current_settings']['absolute'],
-      'language' => isset($settings['language_list'][$settings['langcode']]) ? $settings['language_list'][$settings['langcode']] : $settings['language_list'][LANGUAGE_NONE],
-    )
-  );
   // $matches[1] will be the tag attribute; src, href, etc.
-  return "{$matches[1]}=\"{$url}";
+  return is_string($url) ? "{$matches[1]}=\"{$url}" : $matches[0];
 }