Index: wp-admin/admin-functions.php
===================================================================
--- wp-admin/admin-functions.php	(revision 5063)
+++ wp-admin/admin-functions.php	(working copy)
@@ -1280,6 +1280,7 @@
 	$items = $wpdb->get_results( "SELECT ID, post_parent, post_title FROM $wpdb->posts WHERE post_parent = $parent AND post_type = 'page' ORDER BY menu_order" );
 
 	if ( $items ) {
+		$max_title_length = (int) apply_filters('parent_dropdown_max_title_length', 80);
 		foreach ( $items as $item ) {
 			// A page cannot be its own parent.
 			if (!empty ( $post_ID ) ) {
@@ -1292,6 +1293,10 @@
 				$current = ' selected="selected"';
 			else
 				$current = '';
+			
+			if (strlen($item->post_title) > $max_title_length) {
+				$item->post_title = substr($item->post_title, 0, $max_title_length - 3) . '&8230;';
+			}
 
 			echo "\n\t<option value='$item->ID'$current>$pad $item->post_title</option>";
 			parent_dropdown( $default, $item->ID, $level +1 );