diff --git a/navalplanner-webapp/src/main/java/org/navalplanner/web/common/Util.java b/navalplanner-webapp/src/main/java/org/navalplanner/web/common/Util.java
index dadfb014a..5d7c7211d 100644
--- a/navalplanner-webapp/src/main/java/org/navalplanner/web/common/Util.java
+++ b/navalplanner-webapp/src/main/java/org/navalplanner/web/common/Util.java
@@ -590,12 +590,29 @@ public class Util {
      */
     public static void ensureUniqueListener(Component component, String eventName,
             EventListener uniqueListener) {
+        ensureUniqueListeners(component, eventName, uniqueListener);
+    }
+
+    /**
+     * It removes all listeners registered for eventName and adds the new
+     * listeners. It's ensured that the only listeners left in the component for
+     * events of name eventName is uniqueListeners
+     *
+     * @param component
+     * @param eventName
+     * @param uniqueListeners
+     *            new listeners to add
+     */
+    public static void ensureUniqueListeners(Component component,
+            String eventName, EventListener... uniqueListeners) {
         Iterator<?> listenerIterator = component.getListenerIterator(eventName);
         while (listenerIterator.hasNext()) {
             listenerIterator.next();
             listenerIterator.remove();
         }
-        component.addEventListener(eventName, uniqueListener);
+        for (EventListener each : uniqueListeners) {
+            component.addEventListener(eventName, each);
+        }
     }
 
 }
diff --git a/navalplanner-webapp/src/main/java/org/navalplanner/web/planner/allocation/FormBinder.java b/navalplanner-webapp/src/main/java/org/navalplanner/web/planner/allocation/FormBinder.java
index cde13ebbe..1b0119bdc 100644
--- a/navalplanner-webapp/src/main/java/org/navalplanner/web/planner/allocation/FormBinder.java
+++ b/navalplanner-webapp/src/main/java/org/navalplanner/web/planner/allocation/FormBinder.java
@@ -315,7 +315,7 @@ public class FormBinder {
             this.labelTaskStart = labelTaskStart;
             this.labelTaskEnd = labelTaskEnd;
             initializeDateAndDurationFieldsFromTaskOriginalValues();
-            Util.ensureUniqueListener(taskWorkableDays, Events.ON_CHANGE,
+            Util.ensureUniqueListeners(taskWorkableDays, Events.ON_CHANGE,
                     new EventListener() {
 
                 @Override
@@ -336,9 +336,8 @@ public class FormBinder {
                         showValueOfDateOn(labelTaskStart, newStart);
                     }
                 }
-            });
+                    }, onChangeEnableApply);
             applyDisabledRules();
-            onChangeEnableApply(taskWorkableDays);
         }
 
         void applyDisabledRules() {