Index: wp-admin/includes/schema.php
===================================================================
--- wp-admin/includes/schema.php	(revision 12350)
+++ wp-admin/includes/schema.php	(working copy)
@@ -320,6 +320,12 @@
 	'embed_oembed_discover' => 1,
 	'embed_size_w' => '',
 	'embed_size_h' => 600,
+	'edit_per_page' => 20,
+	'edit_pages_per_page' => 20,
+	'upload_per_page' => 20,
+	'categories_per_page' => 20,
+	'edit_tags_per_page' => 20,
+	'plugins_per_page' => 999,
 	);
 
 	// Set autoload to no for these options