diff --git a/src/main/java/com/gerritforge/gerrit/eventbroker/EventMessage.java b/src/main/java/com/gerritforge/gerrit/eventbroker/EventMessage.java
index 204173e..0684ae4 100644
--- a/src/main/java/com/gerritforge/gerrit/eventbroker/EventMessage.java
+++ b/src/main/java/com/gerritforge/gerrit/eventbroker/EventMessage.java
@@ -48,12 +48,16 @@
     public final UUID eventId;
 
     /** Gerrit server instance id from which event was sent. */
-    public final UUID sourceInstanceId;
+    public final String sourceInstanceId;
 
     /** @deprecated required for interoperability with older JSON wire protocols */
     public final String eventType;
 
     public Header(UUID eventId, UUID sourceInstanceId) {
+      this(eventId, sourceInstanceId.toString());
+    }
+
+    public Header(UUID eventId, String sourceInstanceId) {
       this.eventId = eventId;
       this.sourceInstanceId = sourceInstanceId;
       this.eventType = "";