--- a/nashorn/src/jdk/nashorn/internal/parser/Parser.java	Wed Sep 04 19:58:16 2013 +0530
+++ b/nashorn/src/jdk/nashorn/internal/parser/Parser.java	Thu Sep 05 21:17:06 2013 +0530
@@ -2060,7 +2060,7 @@
         case FLOATING:
             return getLiteral();
         default:
-            return getIdentifierName();
+            return getIdentifierName().setIsPropertyName();
         }
     }
 

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/nashorn/test/script/basic/JDK-8024255.js	Thu Sep 05 21:17:06 2013 +0530
@@ -0,0 +1,51 @@
+/*
+ * Copyright (c) 2010, 2013, Oracle and/or its affiliates. All rights reserved.
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
+ * 
+ * This code is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 only, as
+ * published by the Free Software Foundation.
+ * 
+ * This code is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+ * version 2 for more details (a copy is included in the LICENSE file that
+ * accompanied this code).
+ * 
+ * You should have received a copy of the GNU General Public License version
+ * 2 along with this work; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+ * 
+ * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
+ * or visit www.oracle.com if you need additional information or have any
+ * questions.
+ */
+
+/**
+ * JDK-8024255: When a keyword is used as object property name, the property can not be deleted
+ *
+ * @test
+ * @run
+ */
+
+function check(obj, name) {
+    var desc = Object.getOwnPropertyDescriptor(obj, name);
+    if (! desc.configurable) {
+        fail("Property " + name + " is not configurable");
+    }
+
+    if (! (delete obj[name])) {
+        fail("Property " + name + " can not be deleted");
+    }
+}
+
+var obj = { 
+    default: 344,
+    in: 'hello', 
+    if: false,
+    class: 4.223
+}
+
+for (var p in obj) {
+    check(obj, p);
+}