Add support for 410 error code

Hi! Would be possible to add a setting to configure this module to return a 410 error instead of a 404?
Currently I'm using a custom version of the module, this is a simple patch for 7.x-1.3 but there are many ways to implement this feature.

Implement 410 errors

.--- fast_404.inc       2012-07-20 23:39:49.000000000 +0200
+++ fast_404.inc.new    2012-07-20 23:39:41.000000000 +0200
@@ -70,7 +70,7 @@
 
   // Determine if URL is in blacklisted extensions.
   if ($exts && preg_match($exts, $_SERVER[$server_var], $m)) {
-    fast_404_error_return();
+    fast_404_error_return(FALSE, variable_get('fast_404_return_gone', FALSE));
   }
 
   define('FAST_404_EXT_CHECKED', TRUE);
@@ -95,7 +95,7 @@
   }
 
   if (!$valid) {
-    fast_404_error_return(TRUE);
+    fast_404_error_return(TRUE, variable_get('fast_404_return_gone', FALSE));
   }
 
   define('FAST_404_PATH_CHECKED', TRUE);
@@ -219,8 +219,14 @@
 /**
  * Output our super plain error and exit
  */
-function fast_404_error_return($load_html = FALSE) {
-  header('HTTP/1.0 404 Not Found');
+function fast_404_error_return($load_html = FALSE, $return_gone = FALSE) {
+
+  if ($return_gone){
+    header('HTTP/1.0 410 Gone');
+  } else {
+    header('HTTP/1.0 404 Not Found');
+  }
+  
   
   // If a file is set to provide us with fast_404 joy, load it
   if (($load_html || variable_get('fast_404_HTML_error_all_paths', FALSE)) 

New setting
Add this variable to settings.php to enable "410 Gone" errors instead of "404 Not Found"

$conf['fast_404_return_gone'] = TRUE;

HTML output
Moreover the page HTML should be modified in order to display the new error message.

Thanks for the attention and thanks for implementing this module!