diff --git a/JSONObject.java b/JSONObject.java
index f8ee3590e..3cc6dcba3 100755
--- a/JSONObject.java
+++ b/JSONObject.java
@@ -31,7 +31,7 @@ of this software and associated documentation files (the "Software"), to deal
 import java.lang.reflect.Method;
 import java.util.Collection;
 import java.util.Enumeration;
-import java.util.HashMap;
+import java.util.TreeMap;
 import java.util.Iterator;
 import java.util.Locale;
 import java.util.Map;
@@ -144,7 +144,7 @@ public String toString() {
      * Construct an empty JSONObject.
      */
     public JSONObject() {
-        this.map = new HashMap();
+        this.map = new TreeMap();
     }
 
 
@@ -233,7 +233,7 @@ public JSONObject(JSONTokener x) throws JSONException {
      * @throws JSONException
      */
     public JSONObject(Map map) {
-        this.map = new HashMap();
+        this();
         if (map != null) {
             Iterator i = map.entrySet().iterator();
             while (i.hasNext()) {