diff --git a/lib/test-server/client/slave-client.js b/lib/test-server/client/slave-client.js
index 023807a..04d14ea 100644
--- a/lib/test-server/client/slave-client.js
+++ b/lib/test-server/client/slave-client.js
@@ -187,7 +187,9 @@
     var checkTaskExecutionId = function (scope, name) {
         var res = currentTask && scope.__taskExecutionId === currentTask.taskExecutionId;
         if (!res) {
-            log("<i>warning</i> ignoring call to attester." + name + " for a task that is not valid.");
+            var message = "ignoring call to attester." + name + " for a task that is not (or no longer) valid.";
+            reportLogToServer("warn", [message]);
+            log("<i>warning</i> " + message);
         }
         return res;
     };
diff --git a/lib/test-server/slave-server.js b/lib/test-server/slave-server.js
index 9e0fde9..99aca3f 100644
--- a/lib/test-server/slave-server.js
+++ b/lib/test-server/slave-server.js
@@ -201,12 +201,12 @@ Slave.prototype.assignTask = function (campaign, task) {
 
 Slave.prototype.onTestUpdate = function (event, taskExecutionId) {
     var eventName = event.event;
-    if (eventName == "error" && this.config.taskRestartOnFailure) {
-        this.currentTaskRestartPlanned = true;
+    if (!this.checkTaskExecutionId(taskExecutionId, eventName)) {
+        return;
     }
     if (allowedTestUpdateEvents.hasOwnProperty(eventName)) {
-        if (!this.checkTaskExecutionId(taskExecutionId)) {
-            return;
+        if (eventName == "error" && this.config.taskRestartOnFailure) {
+            this.currentTaskRestartPlanned = true;
         }
         feedEventWithTaskData(event, this.currentTask);
         this.currentCampaign.addResult(event);
@@ -257,14 +257,18 @@ Slave.prototype.onClientLog = function (event, taskExecutionId) {
 };
 
 Slave.prototype.onTaskFinished = function (taskExecutionId) {
-    if (!this.checkTaskExecutionId(taskExecutionId)) {
+    if (!this.checkTaskExecutionId(taskExecutionId, "taskFinished")) {
         return;
     }
     campaignTaskFinished(this);
 };
 
-Slave.prototype.checkTaskExecutionId = function (taskExecutionId) {
-    return taskExecutionId === this.taskExecutionId;
+Slave.prototype.checkTaskExecutionId = function (taskExecutionId, eventName) {
+    var res = taskExecutionId === this.taskExecutionId;
+    if (!res) {
+        this.logger.logWarn("Ignoring %s event from a previous task, not filtered by the client.", [eventName]);
+    }
+    return res;
 };
 
 Slave.prototype.disconnect = function () {