Index: wp-includes/js/wp-lists.dev.js
===================================================================
--- wp-includes/js/wp-lists.dev.js	(revision 21691)
+++ wp-includes/js/wp-lists.dev.js	(working copy)
@@ -78,7 +78,7 @@
 		if ( !s )
 			return false;
 
-		if ( !e.is('[class^="add:' + list.id + ':"]') )
+		if ( !e.is('[id="' + s.what + '-add-submit"]') )
 			return !wpList.add.call( list, e, s );
 
 		if ( !s.element )
Index: wp-admin/includes/meta-boxes.php
===================================================================
--- wp-admin/includes/meta-boxes.php	(revision 21691)
+++ wp-admin/includes/meta-boxes.php	(working copy)
@@ -688,7 +688,7 @@
 		<p id="link-category-add" class="wp-hidden-child">
 			<label class="screen-reader-text" for="newcat"><?php _e( '+ Add New Category' ); ?></label>
 			<input type="text" name="newcat" id="newcat" class="form-required form-input-tip" value="<?php esc_attr_e( 'New category name' ); ?>" aria-required="true" />
-			<input type="button" id="category-add-submit" class="add:categorychecklist:linkcategorydiv button" value="<?php esc_attr_e( 'Add' ); ?>" />
+			<input type="button" id="link-category-add-submit" class="add:categorychecklist:linkcategorydiv button" value="<?php esc_attr_e( 'Add' ); ?>" />
 			<?php wp_nonce_field( 'add-link-category', '_ajax_nonce', false ); ?>
 			<span id="category-ajax-response"></span>
 		</p>
Index: wp-admin/js/link.dev.js
===================================================================
--- wp-admin/js/link.dev.js	(revision 21691)
+++ wp-admin/js/link.dev.js	(working copy)
@@ -23,7 +23,7 @@
 
 	// Ajax Cat
 	newCat = $('#newcat').one( 'focus', function() { $(this).val( '' ).removeClass( 'form-input-tip' ) } );
-	$('#category-add-submit').click( function() { newCat.focus(); } );
+	$('#link-category-add-submit').click( function() { newCat.focus(); } );
 	syncChecks = function() {
 		if ( noSyncChecks )
 			return;