Index: includes/path.inc
===================================================================
RCS file: /cvs/drupal/drupal/includes/path.inc,v
retrieving revision 1.24
diff -u -p -r1.24 path.inc
--- includes/path.inc	24 Jun 2008 22:12:15 -0000	1.24
+++ includes/path.inc	15 Sep 2008 15:32:34 -0000
@@ -52,7 +52,7 @@ function drupal_lookup_path($action, $pa
 
   // Use $count to avoid looking up paths in subsequent calls if there simply are no aliases
   if (!isset($count)) {
-    $count = db_result(db_query('SELECT COUNT(pid) FROM {url_alias}'));
+    $count = db_table_exists('url_alias') ? db_result(db_query('SELECT COUNT(pid) FROM {url_alias}')) : 0;
   }
 
   if ($action == 'wipe') {
Index: modules/path/path.install
===================================================================
RCS file: modules/path/path.install
diff -N modules/path/path.install
--- /dev/null	1 Jan 1970 00:00:00 -0000
+++ modules/path/path.install	15 Sep 2008 15:32:34 -0000
@@ -0,0 +1,65 @@
+<?php
+// $Id$
+
+/**
+ * Implementation of hook_schema().
+ */
+function path_schema() {
+  $schema['url_alias'] = array(
+    'description' => t('A list of URL aliases for Drupal paths; a user may visit either the source or destination path.'),
+    'fields' => array(
+      'pid' => array(
+        'description' => t('A unique path alias identifier.'),
+        'type' => 'serial',
+        'unsigned' => TRUE,
+        'not null' => TRUE,
+      ),
+      'src' => array(
+        'description' => t('The Drupal path this alias is for; e.g. node/12.'),
+        'type' => 'varchar',
+        'length' => 128,
+        'not null' => TRUE,
+        'default' => '',
+      ),
+      'dst' => array(
+        'description' => t('The alias for this path; e.g. title-of-the-story.'),
+        'type' => 'varchar',
+        'length' => 128,
+        'not null' => TRUE,
+        'default' => '',
+      ),
+      'language' => array(
+        'description' => t('The language this alias is for; if blank, the alias will be used for unknown languages. Each Drupal path can have an alias for each supported language.'),
+        'type' => 'varchar',
+        'length' => 12,
+        'not null' => TRUE,
+        'default' => '',
+      ),
+    ),
+    'unique keys' => array(
+      'dst_language' => array('dst', 'language'),
+    ),
+    'primary key' => array('pid'),
+    'indexes' => array(
+      'src' => array('src'),
+    ),
+  );
+
+  return $schema;
+}
+
+/**
+ * Implementation of hook_install().
+ */
+function path_install() {
+  if (!db_table_exists('url_alias')) {
+    drupal_install_schema('path');
+  }
+}
+
+/**
+ * Implementation of hook_uninstall().
+ */
+function path_uninstall() {
+  drupal_uninstall_schema('path');
+}
Index: modules/system/system.install
===================================================================
RCS file: /cvs/drupal/drupal/modules/system/system.install,v
retrieving revision 1.264
diff -u -p -r1.264 system.install
--- modules/system/system.install	15 Sep 2008 09:28:50 -0000	1.264
+++ modules/system/system.install	15 Sep 2008 15:32:39 -0000
@@ -1239,46 +1239,6 @@ function system_schema() {
     ),
   );
 
-  $schema['url_alias'] = array(
-    'description' => t('A list of URL aliases for Drupal paths; a user may visit either the source or destination path.'),
-    'fields' => array(
-      'pid' => array(
-        'description' => t('A unique path alias identifier.'),
-        'type' => 'serial',
-        'unsigned' => TRUE,
-        'not null' => TRUE,
-      ),
-      'src' => array(
-        'description' => t('The Drupal path this alias is for; e.g. node/12.'),
-        'type' => 'varchar',
-        'length' => 128,
-        'not null' => TRUE,
-        'default' => '',
-      ),
-      'dst' => array(
-        'description' => t('The alias for this path; e.g. title-of-the-story.'),
-        'type' => 'varchar',
-        'length' => 128,
-        'not null' => TRUE,
-        'default' => '',
-      ),
-      'language' => array(
-        'description' => t('The language this alias is for; if blank, the alias will be used for unknown languages. Each Drupal path can have an alias for each supported language.'),
-        'type' => 'varchar',
-        'length' => 12,
-        'not null' => TRUE,
-        'default' => '',
-      ),
-    ),
-    'unique keys' => array(
-      'dst_language' => array('dst', 'language'),
-    ),
-    'primary key' => array('pid'),
-    'indexes' => array(
-      'src' => array('src'),
-    ),
-  );
-
   return $schema;
 }