diff --git a/src/main/java/org/msgpack/util/json/JSONUnpacker.java b/src/main/java/org/msgpack/util/json/JSONUnpacker.java
index 177bf2230..864c5ca18 100644
--- a/src/main/java/org/msgpack/util/json/JSONUnpacker.java
+++ b/src/main/java/org/msgpack/util/json/JSONUnpacker.java
@@ -24,6 +24,7 @@
 import java.util.List;
 import java.util.Map;
 import java.util.Iterator;
+import java.nio.charset.Charset;
 import org.json.simple.parser.JSONParser;
 import org.json.simple.parser.ParseException;
 import org.msgpack.MessagePack;
@@ -42,6 +43,10 @@ public JSONUnpacker(InputStream in) {
     public JSONUnpacker(MessagePack msgpack, InputStream in) {
         this(msgpack, new InputStreamReader(in));
     }
+    
+    public JSONUnpacker(MessagePack msgpack, InputStream in, Charset cs) {
+        this(msgpack, new InputStreamReader(in, cs));
+    }
 
     JSONUnpacker(MessagePack msgpack, Reader in) {
         super(msgpack, null);