diff --git a/src/main/java/org/jenkinsci/lib/envinject/EnvInjectAction.java b/src/main/java/org/jenkinsci/lib/envinject/EnvInjectAction.java
index 5af5f02..b4ebbbb 100644
--- a/src/main/java/org/jenkinsci/lib/envinject/EnvInjectAction.java
+++ b/src/main/java/org/jenkinsci/lib/envinject/EnvInjectAction.java
@@ -132,7 +132,7 @@ public String getUrlName() {
     }
 
     @SuppressWarnings("unused")
-    private Object writeReplace() throws ObjectStreamException {
+    protected Object writeReplace() throws ObjectStreamException {
         try {
             EnvInjectSavable dao = new EnvInjectSavable();