diff -u -r1.9 UserBlockPlugin.inc.php
--- plugins/blocks/user/UserBlockPlugin.inc.php	8 Apr 2009 19:54:36 -0000	1.9
+++ plugins/blocks/user/UserBlockPlugin.inc.php	20 Jan 2010 00:10:05 -0000
@@ -22,6 +22,7 @@
 		$success = parent::register($category, $path);
 		if ($success) {
 			$this->addLocaleData();
+			Locale::requireComponents(array(LOCALE_COMPONENT_PKP_USER));
 		}
 		return $success;
 	}