diff --git a/inmem.go b/inmem.go
index 14c46ca..a6f0dd1 100644
--- a/inmem.go
+++ b/inmem.go
@@ -430,14 +430,15 @@ func (w *pipeSender) copyStructure(m interface{}) (interface{}, error) {
 }
 
 func (w *pipeSender) copyStructValue(v reflect.Value) (interface{}, error) {
-	mCopy := make(map[string]interface{})
-	t := v.Type()
+	mCopy := reflect.New(v.Type()).Elem()
 	for i := 0; i < v.NumField(); i++ {
 		vCopy, vErr := w.copyValue(v.Field(i).Interface())
 		if vErr != nil {
 			return nil, vErr
 		}
-		mCopy[t.Field(i).Name] = vCopy
+		if vCopy != nil {
+			mCopy.Field(i).Set(reflect.ValueOf(vCopy))
+		}
 	}
-	return mCopy, nil
+	return mCopy.Interface(), nil
 }