msgpack.cc.diff

diff --git a/src/msgpack.cc b/src/msgpack.cc
index 0803d67..818fe5d 100644
--- a/src/msgpack.cc
+++ b/src/msgpack.cc
@@ -288,8 +288,7 @@ pack(const Arguments &args) {
         }
     }
 
-    Buffer *bp = Buffer::New(sb._sbuf.size);
-    memcpy(bp->data(), sb._sbuf.data, sb._sbuf.size);
+    Buffer *bp = Buffer::New(sb._sbuf.data, sb._sbuf.size);
 
     return scope.Close(bp->handle_);
 }
@@ -311,19 +310,19 @@ unpack(const Arguments &args) {
             String::New("First argument must be a Buffer")));
     }
 
-    Buffer *buf = ObjectWrap::Unwrap<Buffer>(args[0]->ToObject());
+    Handle<Object> buf = args[0]->ToObject();
 
     MsgpackZone mz;
     msgpack_object mo;
     size_t off = 0;
 
-    switch (msgpack_unpack(buf->data(), buf->length(), &off, &mz._mz, &mo)) {
+    switch (msgpack_unpack(Buffer::Data(buf), Buffer::Length(buf), &off, &mz._mz, &mo)) {
     case MSGPACK_UNPACK_EXTRA_BYTES:
     case MSGPACK_UNPACK_SUCCESS:
         try {
             msgpack_unpack_template->GetFunction()->Set(
                 msgpack_bytes_remaining_symbol,
-                Integer::New(buf->length() - off)
+                Integer::New(Buffer::Length(buf) - off)
             );
             return scope.Close(msgpack_to_v8(&mo));
         } catch (MsgpackException e) {