diff --git a/impl/src/main/java/com/sun/el/parser/ELParser.jjt b/impl/src/main/java/com/sun/el/parser/ELParser.jjt
index 703f6ef..4cccc57 100644
--- a/impl/src/main/java/com/sun/el/parser/ELParser.jjt
+++ b/impl/src/main/java/com/sun/el/parser/ELParser.jjt
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 1997, 2018 Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 1997, 2021 Oracle and/or its affiliates. All rights reserved.
  *
  * This program and the accompanying materials are made available under the
  * terms of the Eclipse Public License v. 2.0, which is available at
@@ -453,8 +453,8 @@
   < LITERAL_EXPRESSION:
     ((~["\\", "$", "#"])
       | ("\\" ("\\" | "$" | "#"))
-      | ("$" ~["{", "$", "#"])
-      | ("#" ~["{", "$", "#"])
+      | ("$" ~["{", "$", "#", "\\"])
+      | ("#" ~["{", "$", "#", "\\"])
     )+
     | "$"
     | "#"
diff --git a/impl/src/main/java/com/sun/el/parser/ELParserTokenManager.java b/impl/src/main/java/com/sun/el/parser/ELParserTokenManager.java
index 0c59560..027fd5d 100644
--- a/impl/src/main/java/com/sun/el/parser/ELParserTokenManager.java
+++ b/impl/src/main/java/com/sun/el/parser/ELParserTokenManager.java
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2018 Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2018, 2021 Oracle and/or its affiliates. All rights reserved.
  *
  * This program and the accompanying materials are made available under the
  * terms of the Eclipse Public License v. 2.0, which is available at
@@ -205,7 +205,7 @@
                         jjCheckNAddStates(0, 3);
                         break;
                     case 4:
-                        if ((0xf7ffffffffffffffL & l) == 0L) {
+                        if ((0xf7ffffffefffffffL & l) == 0L) {
                             break;
                         }
                         if (kind > 1) {
diff --git a/src/test/java/org/glassfish/el/test/EscapingTest.java b/src/test/java/org/glassfish/el/test/EscapingTest.java
new file mode 100644
index 0000000..4f78bd7
--- /dev/null
+++ b/src/test/java/org/glassfish/el/test/EscapingTest.java
@@ -0,0 +1,71 @@
+/*
+ * Copyright (c) 2021 Oracle and/or its affiliates. All rights reserved.
+ *
+ * This program and the accompanying materials are made available under the
+ * terms of the Eclipse Public License v. 2.0, which is available at
+ * http://www.eclipse.org/legal/epl-2.0.
+ *
+ * This Source Code may also be made available under the following Secondary
+ * Licenses when the conditions for such availability set forth in the
+ * Eclipse Public License v. 2.0 are satisfied: GNU General Public License,
+ * version 2 with the GNU Classpath Exception, which is available at
+ * https://www.gnu.org/software/classpath/license.html.
+ *
+ * SPDX-License-Identifier: EPL-2.0 OR GPL-2.0 WITH Classpath-exception-2.0
+ */
+
+package org.glassfish.el.test;
+
+import javax.el.ELManager;
+import javax.el.ELProcessor;
+import javax.el.ValueExpression;
+import org.junit.Assert;
+import org.junit.BeforeClass;
+import org.junit.Test;
+
+import static org.junit.Assert.assertEquals;
+
+public class EscapingTest {
+
+    static ELProcessor elp;
+    static ELManager elm;
+
+    public EscapingTest() {
+    }
+
+    @BeforeClass
+    public static void setUpClass() throws Exception {
+        elp = new ELProcessor();
+        elm = elp.getELManager();
+    }
+
+    @Test
+    public void testEscape01() {
+        assertEquals("$2", evaluateExpression("$${1+1}"));
+        assertEquals("$${1+1}", evaluateExpression("$\\${1+1}"));
+    }
+
+    @Test
+    public void testEscape02() {
+        assertEquals("$2", evaluateExpression("$#{1+1}"));
+        assertEquals("$#{1+1}", evaluateExpression("$\\#{1+1}"));
+    }
+
+    @Test
+    public void testEscape03() {
+        assertEquals("#2", evaluateExpression("##{1+1}"));
+        assertEquals("##{1+1}", evaluateExpression("#\\#{1+1}"));
+    }
+
+    @Test
+    public void testEscape04() {
+        assertEquals("#2", evaluateExpression("#${1+1}"));
+        assertEquals("#${1+1}", evaluateExpression("#\\${1+1}"));
+    }
+
+    private String evaluateExpression(String expr) {
+        ValueExpression v = ELManager.getExpressionFactory().createValueExpression(
+                elm.getELContext(), expr, String.class);
+        return (String) v.getValue(elm.getELContext());
+    }
+}