diff --git a/src/common/eventmeth.cc b/src/common/eventmeth.cc
index bd5b114c9..e49fd54da 100644
--- a/src/common/eventmeth.cc
+++ b/src/common/eventmeth.cc
@@ -4037,6 +4037,8 @@ EmEventTmrFd::EmEventTmrFd(clockid_t clock_id,
 
         if (ctl_res == 0)
         {
+            GUARD_AND_DBG_LOG(interest_mutex_);
+            
             switch(op)
             {
             case EvCtlAction::Add:
diff --git a/version.txt b/version.txt
index 36f87cbe5..57a3b2c0f 100644
--- a/version.txt
+++ b/version.txt
@@ -1 +1 @@
-0.4.1.20240828
+0.4.2.20240829