Index: wp-admin/nav-menus.php
===================================================================
--- wp-admin/nav-menus.php	(revision 14373)
+++ wp-admin/nav-menus.php	(working copy)
@@ -302,6 +302,11 @@
 	$nav_menu_selected_title = ! is_wp_error( $_menu_object ) ? $_menu_object->name : '';
 }
 
+// Generate truncated menu names
+foreach( (array) $nav_menus as $_nav_menu ) {
+	$_nav_menu->truncated_name = ( strlen($_nav_menu->name) > 40 ) ? substr( $_nav_menu->name, 0, 40 ) . '...' : $_nav_menu->name;
+}
+
 // The theme supports menus
 if ( current_theme_supports('nav-menus') ) {
 	// Set up nav menu
@@ -353,7 +358,7 @@
 					<select id="select-nav-menu" name="menu">
 						<?php foreach( (array) $nav_menus as $_nav_menu ) : ?>
 							<option value="<?php echo esc_attr($_nav_menu->term_id) ?>" <?php selected($nav_menu_selected_id, $_nav_menu->term_id); ?>>
-								<?php echo esc_html( $_nav_menu->name ); ?>
+							<?php echo esc_html( $_nav_menu->truncated_name ); ?>
 							</option>
 						<?php endforeach; ?>
 						<option value="0"><?php esc_html_e('Add New Menu'); ?></option>
@@ -380,7 +385,7 @@
 							echo ' nav-tab-active';
 						else
 							echo ' hide-if-no-js';
-					?>"><?php echo esc_html( $_nav_menu->name ); ?></a><?php
+					?>"><?php echo esc_html( $_nav_menu->truncated_name )?></a><?php
 				endforeach;
 				?><a href="<?php 
 					echo add_query_arg(