the "nurl" index was accidentally dropped

database.sql

@@ -334,6 +334,7 @@ CREATE TABLE IF NOT EXISTS `gcontact` (
 	`generation` tinyint(3) NOT NULL DEFAULT 0,
 	`server_url` varchar(255) NOT NULL DEFAULT '',
 	 PRIMARY KEY(`id`),
+	 INDEX `nurl` (`nurl`),
 	 INDEX `name` (`name`),
 	 INDEX `nick` (`nick`),
 	 INDEX `addr` (`addr`),

include/dbstructure.php

@@ -670,6 +670,7 @@ function db_definition() {
 					),
 			"indexes" => array(
 					"PRIMARY" => array("id"),
+					"nurl" => array("nurl"),
 					"name" => array("name"),
 					"nick" => array("nick"),
 					"addr" => array("addr"),