Index: includes/path.inc
===================================================================
RCS file: /cvs/drupal/drupal/includes/path.inc,v
retrieving revision 1.13
diff -u -p -r1.13 path.inc
--- includes/path.inc	23 Dec 2006 22:04:52 -0000	1.13
+++ includes/path.inc	3 Jan 2007 14:50:24 -0000
@@ -54,11 +54,18 @@ function drupal_lookup_path($action, $pa
     $no_src = array();
   }
   elseif ($count > 0 && $path != '') {
+    static $skiplist;
+
+    // Use $skiplist to avoid retrieving the skiplist every time in subsequent calls
+    if (!isset($skiplist)) {
+      $skiplist = variable_get('path_skiplist', '');
+    }
+
     if ($action == 'alias') {
       if (isset($map[$path])) {
         return $map[$path];
       }
-      $alias = db_result(db_query("SELECT dst FROM {url_alias} WHERE src = '%s'", $path));
+      $alias = drupal_path_match_patterns($path, $skiplist) ? FALSE : db_result(db_query("SELECT dst FROM {url_alias} WHERE src = '%s'", $path));
       $map[$path] = $alias;
       return $alias;
     }
@@ -67,7 +74,10 @@ function drupal_lookup_path($action, $pa
     elseif ($action == 'source' && !isset($no_src[$path])) {
       // Look for the value $path within the cached $map
       if (!$src = array_search($path, $map)) {
-        if ($src = db_result(db_query("SELECT src FROM {url_alias} WHERE dst = '%s'", $path))) {
+        if (drupal_path_match_patterns($path, $skiplist)) {
+            $map[$src] = $path;
+          }
+          elseif ($src = db_result(db_query("SELECT src FROM {url_alias} WHERE dst = '%s'", $path))) {
           $map[$src] = $path;
         }
         else {
@@ -205,3 +215,19 @@ function drupal_is_front_page() {
   // we can check it against the 'site_frontpage' variable.
   return $_GET['q'] == drupal_get_normal_path(variable_get('site_frontpage', 'node'));
 }
+
+/**
+ * Check if a path matches a path in the skiplist.
+ *
+ * @param $path
+ *   The path to match.
+ * @param $patterns
+ *  String containing patterns separated by \n, \r or \r\n.
+ *
+ * @return
+ *   Boolean value: TRUE if the path matches a path in the skiplist, FALSE if otherwise.
+ */
+function drupal_path_match_patterns($path, $patterns) {
+  $regexp = '/^('. preg_replace(array('/(\r\n?|\n)/', '/\\\\\*/', '/(^|\|)\\\\<front\\\\>($|\|)/'), array('|', '.*', '\1'. preg_quote(variable_get('site_frontpage', 'node'), '/') .'\2'), preg_quote($patterns, '/')) .')$/';
+  return  preg_match($regexp, $path);
+}
\ No newline at end of file
Index: modules/block/block.module
===================================================================
RCS file: /cvs/drupal/drupal/modules/block/block.module,v
retrieving revision 1.245
diff -u -p -r1.245 block.module
--- modules/block/block.module	18 Dec 2006 21:49:39 -0000	1.245
+++ modules/block/block.module	3 Jan 2007 14:50:25 -0000
@@ -663,11 +663,10 @@ function block_list($region) {
       if ($block->pages) {
         if ($block->visibility < 2) {
           $path = drupal_get_path_alias($_GET['q']);
-          $regexp = '/^('. preg_replace(array('/(\r\n?|\n)/', '/\\\\\*/', '/(^|\|)\\\\<front\\\\>($|\|)/'), array('|', '.*', '\1'. preg_quote(variable_get('site_frontpage', 'node'), '/') .'\2'), preg_quote($block->pages, '/')) .')$/';
           // Compare with the internal and path alias (if any).
-          $page_match = preg_match($regexp, $path);
+          $page_match = drupal_path_match_patterns($path, $block->pages);
           if ($path != $_GET['q']) {
-            $page_match = $page_match || preg_match($regexp, $_GET['q']);
+            $page_match = $page_match || drupal_path_match_patterns($_GET['q'], $block->pages);
           }
           // When $block->visibility has a value of 0, the block is displayed on
           // all pages except those listed in $block->pages. When set to 1, it