diff --git a/src/test/java/org/jboss/netty/util/DebugUtilTest.java b/src/test/java/org/jboss/netty/util/DebugUtilTest.java
new file mode 100644
index 0000000000..acc4ab6879
--- /dev/null
+++ b/src/test/java/org/jboss/netty/util/DebugUtilTest.java
@@ -0,0 +1,232 @@
+/*
+ * JBoss, Home of Professional Open Source
+ *
+ * Copyright 2008, Red Hat Middleware LLC, and individual contributors
+ * by the @author tags. See the COPYRIGHT.txt in the distribution for a
+ * full listing of individual contributors.
+ *
+ * This is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU Lesser General Public License as
+ * published by the Free Software Foundation; either version 2.1 of
+ * the License, or (at your option) any later version.
+ *
+ * This software 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
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this software; if not, write to the Free
+ * Software Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
+ * 02110-1301 USA, or see the FSF site: http://www.fsf.org.
+ */
+package org.jboss.netty.util;
+
+import static org.junit.Assert.*;
+
+import java.io.FileDescriptor;
+import java.net.InetAddress;
+import java.security.Permission;
+
+import org.junit.After;
+import org.junit.Before;
+import org.junit.Test;
+
+
+/**
+ * @author The Netty Project (netty-dev@lists.jboss.org)
+ * @author Trustin Lee (tlee@redhat.com)
+ *
+ * @version $Rev$, $Date$
+ *
+ */
+public class DebugUtilTest {
+
+    public void shouldReturnFalseIfPropertyIsNotSet() {
+        assertFalse(DebugUtil.isDebugEnabled());
+    }
+
+    @Test
+    public void shouldReturnTrueInDebugMode() {
+        System.setProperty("org.jboss.netty.debug", "true");
+        assertTrue(DebugUtil.isDebugEnabled());
+    }
+
+    @Test
+    public void shouldReturnFalseInNonDebugMode() {
+        System.setProperty("org.jboss.netty.debug", "false");
+        assertFalse(DebugUtil.isDebugEnabled());
+    }
+
+    @Test
+    public void shouldNotBombOutWhenSecurityManagerIsInAction() {
+        System.setProperty("org.jboss.netty.debug", "true");
+        System.setSecurityManager(new SecurityManager() {
+            @Override
+            public void checkPropertyAccess(String key) {
+                throw new SecurityException();
+            }
+
+            @Override
+            public void checkAccept(String host, int port) {
+                // Allow
+            }
+
+            @Override
+            public void checkAccess(Thread t) {
+                // Allow
+            }
+
+            @Override
+            public void checkAccess(ThreadGroup g) {
+                // Allow
+            }
+
+            @Override
+            public void checkAwtEventQueueAccess() {
+                // Allow
+            }
+
+            @Override
+            public void checkConnect(String host, int port, Object context) {
+                // Allow
+            }
+
+            @Override
+            public void checkConnect(String host, int port) {
+                // Allow
+            }
+
+            @Override
+            public void checkCreateClassLoader() {
+                // Allow
+            }
+
+            @Override
+            public void checkDelete(String file) {
+                // Allow
+            }
+
+            @Override
+            public void checkExec(String cmd) {
+                // Allow
+            }
+
+            @Override
+            public void checkExit(int status) {
+                // Allow
+            }
+
+            @Override
+            public void checkLink(String lib) {
+                // Allow
+            }
+
+            @Override
+            public void checkListen(int port) {
+                // Allow
+            }
+
+            @Override
+            public void checkMemberAccess(Class<?> clazz, int which) {
+                // Allow
+            }
+
+            @Override
+            public void checkMulticast(InetAddress maddr, byte ttl) {
+                // Allow
+            }
+
+            @Override
+            public void checkMulticast(InetAddress maddr) {
+                // Allow
+            }
+
+            @Override
+            public void checkPackageAccess(String pkg) {
+                // Allow
+            }
+
+            @Override
+            public void checkPackageDefinition(String pkg) {
+                // Allow
+            }
+
+            @Override
+            public void checkPermission(Permission perm, Object context) {
+                // Allow
+            }
+
+            @Override
+            public void checkPermission(Permission perm) {
+                // Allow
+            }
+
+            @Override
+            public void checkPrintJobAccess() {
+                // Allow
+            }
+
+            @Override
+            public void checkPropertiesAccess() {
+                // Allow
+            }
+
+            @Override
+            public void checkRead(FileDescriptor fd) {
+                // Allow
+            }
+
+            @Override
+            public void checkRead(String file, Object context) {
+                // Allow
+            }
+
+            @Override
+            public void checkRead(String file) {
+                // Allow
+            }
+
+            @Override
+            public void checkSecurityAccess(String target) {
+                // Allow
+            }
+
+            @Override
+            public void checkSetFactory() {
+                // Allow
+            }
+
+            @Override
+            public void checkSystemClipboardAccess() {
+                // Allow
+            }
+
+            @Override
+            public boolean checkTopLevelWindow(Object window) {
+                return true;
+            }
+
+            @Override
+            public void checkWrite(FileDescriptor fd) {
+                // Allow
+            }
+
+            @Override
+            public void checkWrite(String file) {
+                // Allow
+            }
+        });
+        try {
+            assertFalse(DebugUtil.isDebugEnabled());
+        } finally {
+            System.setSecurityManager(null);
+        }
+
+    }
+
+    @Before @After
+    public void cleanup() {
+        System.clearProperty("org.jboss.netty.debug");
+    }
+}