diff --git a/buffer/src/main/java/io/netty/buffer/PoolArena.java b/buffer/src/main/java/io/netty/buffer/PoolArena.java
index 8b24c3711b..5f7998e662 100644
--- a/buffer/src/main/java/io/netty/buffer/PoolArena.java
+++ b/buffer/src/main/java/io/netty/buffer/PoolArena.java
@@ -233,6 +233,7 @@ abstract class PoolArena<T> {
             // Doubled
 
             int normalizedCapacity = reqCapacity;
+            normalizedCapacity --;
             normalizedCapacity |= normalizedCapacity >>>  1;
             normalizedCapacity |= normalizedCapacity >>>  2;
             normalizedCapacity |= normalizedCapacity >>>  4;
diff --git a/buffer/src/test/java/io/netty/buffer/PoolArenaTest.java b/buffer/src/test/java/io/netty/buffer/PoolArenaTest.java
new file mode 100644
index 0000000000..f5acd2b4f2
--- /dev/null
+++ b/buffer/src/test/java/io/netty/buffer/PoolArenaTest.java
@@ -0,0 +1,35 @@
+/*
+ * Copyright 2012 The Netty Project
+ *
+ * The Netty Project licenses this file to you under the Apache License,
+ * version 2.0 (the "License"); you may not use this file except in compliance
+ * with the License. You may obtain a copy of the License at:
+ *
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+ * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
+ * License for the specific language governing permissions and limitations
+ * under the License.
+ */
+
+package io.netty.buffer;
+
+import org.junit.Assert;
+import org.junit.Test;
+
+import java.nio.ByteBuffer;
+
+public class PoolArenaTest {
+
+    @Test
+    public void testNormalizeCapacity() throws Exception {
+        PoolArena<ByteBuffer> arena = new PoolArena.DirectArena(null, 0, 0, 9, 999999);
+        int[] reqCapacities = {0, 15, 510, 1024, 1023, 1025};
+        int[] expectedResult = {0, 16, 512, 1024, 1024, 2048};
+        for (int i = 0; i < reqCapacities.length; i ++) {
+            Assert.assertEquals(expectedResult[i], arena.normalizeCapacity(reqCapacities[i]));
+        }
+    }
+}