diff --git a/src/config_passthrough.cpp b/src/config_passthrough.cpp
index af076c34..73daa050 100644
--- a/src/config_passthrough.cpp
+++ b/src/config_passthrough.cpp
@@ -36,7 +36,7 @@ Passthrough::from_string(const std::string &s_)
   if(!x)
     return -EINVAL;
   
-  _data = x;
+  _data = x->_to_string();
 
   return 0;
 }