diff --git a/ganttzk/src/main/java/org/zkoss/ganttz/data/GanttDiagramGraph.java b/ganttzk/src/main/java/org/zkoss/ganttz/data/GanttDiagramGraph.java
index cc1fdd91d..590ad962b 100644
--- a/ganttzk/src/main/java/org/zkoss/ganttz/data/GanttDiagramGraph.java
+++ b/ganttzk/src/main/java/org/zkoss/ganttz/data/GanttDiagramGraph.java
@@ -79,6 +79,10 @@ public class GanttDiagramGraph<V, D extends IDependency<V>> implements
             public void setStartDate(GanttDate previousStart,
                     GanttDate previousEnd, GanttDate newStart) {
             }
+
+            @Override
+            public void positionPotentiallyModified() {
+            }
         };
     }
 
@@ -555,13 +559,17 @@ public class GanttDiagramGraph<V, D extends IDependency<V>> implements
         }
     }
 
-    public interface IDependenciesEnforcerHook {
+    private interface IDependenciesEnforcer {
         public void setStartDate(GanttDate previousStart,
                 GanttDate previousEnd, GanttDate newStart);
 
         public void setNewEnd(GanttDate previousEnd, GanttDate newEnd);
     }
 
+    public interface IDependenciesEnforcerHook extends IDependenciesEnforcer {
+        public void positionPotentiallyModified();
+    }
+
     public interface IDependenciesEnforcerHookFactory<T> {
         public IDependenciesEnforcerHook create(T task,
                 INotificationAfterDependenciesEnforcement notification);
@@ -708,8 +716,10 @@ public class GanttDiagramGraph<V, D extends IDependency<V>> implements
         @Override
         public IDependenciesEnforcerHook create(V task,
                 INotificationAfterDependenciesEnforcement notificator) {
-            return onlyEnforceDependenciesOnEntrance(onEntrance(task),
-                    onNotification(task, notificator));
+            return withPositionPotentiallyModified(
+                    task,
+                    onlyEnforceDependenciesOnEntrance(onEntrance(task),
+                            onNotification(task, notificator)));
         }
 
         @Override
@@ -717,8 +727,8 @@ public class GanttDiagramGraph<V, D extends IDependency<V>> implements
             return create(task, EMPTY_NOTIFICATOR);
         }
 
-        private IDependenciesEnforcerHook onEntrance(final V task) {
-            return new IDependenciesEnforcerHook() {
+        private IDependenciesEnforcer onEntrance(final V task) {
+            return new IDependenciesEnforcer() {
 
                 public void setStartDate(GanttDate previousStart,
                         GanttDate previousEnd, GanttDate newStart) {
@@ -733,9 +743,9 @@ public class GanttDiagramGraph<V, D extends IDependency<V>> implements
             };
         }
 
-        private IDependenciesEnforcerHook onNotification(final V task,
+        private IDependenciesEnforcer onNotification(final V task,
                 final INotificationAfterDependenciesEnforcement notification) {
-            return new IDependenciesEnforcerHook() {
+            return new IDependenciesEnforcer() {
 
                 @Override
                 public void setStartDate(GanttDate previousStart,
@@ -757,11 +767,33 @@ public class GanttDiagramGraph<V, D extends IDependency<V>> implements
 
         }
 
-        private IDependenciesEnforcerHook onlyEnforceDependenciesOnEntrance(
-                final IDependenciesEnforcerHook onEntrance,
-                final IDependenciesEnforcerHook notification) {
+        private IDependenciesEnforcerHook withPositionPotentiallyModified(
+                final V task, final IDependenciesEnforcer enforcer) {
             return new IDependenciesEnforcerHook() {
 
+                @Override
+                public void setStartDate(GanttDate previousStart,
+                        GanttDate previousEnd, GanttDate newStart) {
+                    enforcer.setStartDate(previousStart, previousEnd, newStart);
+                }
+
+                @Override
+                public void setNewEnd(GanttDate previousEnd, GanttDate newEnd) {
+                    enforcer.setNewEnd(previousEnd, newEnd);
+                }
+
+                @Override
+                public void positionPotentiallyModified() {
+                    taskPositionModified(task);
+                }
+            };
+        }
+
+        private IDependenciesEnforcer onlyEnforceDependenciesOnEntrance(
+                final IDependenciesEnforcer onEntrance,
+                final IDependenciesEnforcer notification) {
+            return new IDependenciesEnforcer() {
+
                 @Override
                 public void setStartDate(final GanttDate previousStart,
                         final GanttDate previousEnd, final GanttDate newStart) {
diff --git a/ganttzk/src/main/java/org/zkoss/ganttz/data/Task.java b/ganttzk/src/main/java/org/zkoss/ganttz/data/Task.java
index ea2cdb1bd..b1f9788a6 100644
--- a/ganttzk/src/main/java/org/zkoss/ganttz/data/Task.java
+++ b/ganttzk/src/main/java/org/zkoss/ganttz/data/Task.java
@@ -85,7 +85,8 @@ public abstract class Task implements ITaskFundamentalProperties {
     private ConstraintViolationNotificator<GanttDate> violationNotificator = ConstraintViolationNotificator
             .create();
 
-    private IDependenciesEnforcerHook dependenciesEnforcerHook = GanttDiagramGraph.doNothingHook();
+    private IDependenciesEnforcerHook dependenciesEnforcerHook = GanttDiagramGraph
+            .doNothingHook();
 
     private final INotificationAfterDependenciesEnforcement notifyDates = new INotificationAfterDependenciesEnforcement() {
 
@@ -258,11 +259,8 @@ public abstract class Task implements ITaskFundamentalProperties {
         Validate.notNull(dependenciesEnforcerHook);
     }
 
-    public void fireChangesForPreviousValues(GanttDate previousStart,
-            GanttDate previousEnd) {
-        dependenciesEnforcerHook.setStartDate(previousStart, previousStart,
-                fundamentalProperties.getBeginDate());
-        dependenciesEnforcerHook.setNewEnd(previousEnd, getEndDate());
+    public void enforceDependenciesDueToPositionPotentiallyModified() {
+        dependenciesEnforcerHook.positionPotentiallyModified();
     }
 
     public GanttDate getBeginDate() {
diff --git a/libreplan-webapp/src/main/java/org/libreplan/web/planner/allocation/ResourceAllocationModel.java b/libreplan-webapp/src/main/java/org/libreplan/web/planner/allocation/ResourceAllocationModel.java
index 433c5dfad..bfd8d0e46 100644
--- a/libreplan-webapp/src/main/java/org/libreplan/web/planner/allocation/ResourceAllocationModel.java
+++ b/libreplan-webapp/src/main/java/org/libreplan/web/planner/allocation/ResourceAllocationModel.java
@@ -188,12 +188,9 @@ public class ResourceAllocationModel implements IResourceAllocationModel {
     private <V, T extends Flagged<V, ?>> T applyDateChangesNotificationIfNoFlags(
             IOnTransaction<T> allocationDoer) {
         org.zkoss.ganttz.data.Task ganttTask = context.getTask();
-        GanttDate previousStartDate = ganttTask.getBeginDate();
-        GanttDate previousEnd = ganttTask.getEndDate();
         T result = transactionService.runOnReadOnlyTransaction(allocationDoer);
         if (!result.isFlagged()) {
-            ganttTask.fireChangesForPreviousValues(previousStartDate,
-                    previousEnd);
+            ganttTask.enforceDependenciesDueToPositionPotentiallyModified();
         }
         return result;
     }
diff --git a/libreplan-webapp/src/main/java/org/libreplan/web/planner/consolidations/AdvanceConsolidationModel.java b/libreplan-webapp/src/main/java/org/libreplan/web/planner/consolidations/AdvanceConsolidationModel.java
index 09e4c1d9a..f08e345ee 100644
--- a/libreplan-webapp/src/main/java/org/libreplan/web/planner/consolidations/AdvanceConsolidationModel.java
+++ b/libreplan-webapp/src/main/java/org/libreplan/web/planner/consolidations/AdvanceConsolidationModel.java
@@ -138,8 +138,6 @@ public class AdvanceConsolidationModel implements IAdvanceConsolidationModel {
     public void accept() {
         if (context != null && orderElement != null && isVisibleAdvances()) {
             org.zkoss.ganttz.data.Task ganttTask = context.getTask();
-            GanttDate previousStartDate = ganttTask.getBeginDate();
-            GanttDate previousEnd = ganttTask.getEndDate();
 
             createConsolidationIfNeeded();
 
@@ -153,8 +151,7 @@ public class AdvanceConsolidationModel implements IAdvanceConsolidationModel {
 
             updateConsolidationInAdvanceIfIsNeeded();
 
-            ganttTask.fireChangesForPreviousValues(previousStartDate,
-                    previousEnd);
+            ganttTask.enforceDependenciesDueToPositionPotentiallyModified();
             ganttTask.reloadResourcesText();
             context.reloadCharts();
         }
diff --git a/libreplan-webapp/src/main/java/org/libreplan/web/planner/limiting/allocation/LimitingResourceAllocationModel.java b/libreplan-webapp/src/main/java/org/libreplan/web/planner/limiting/allocation/LimitingResourceAllocationModel.java
index 995ac2d5f..e48970975 100644
--- a/libreplan-webapp/src/main/java/org/libreplan/web/planner/limiting/allocation/LimitingResourceAllocationModel.java
+++ b/libreplan-webapp/src/main/java/org/libreplan/web/planner/limiting/allocation/LimitingResourceAllocationModel.java
@@ -383,11 +383,8 @@ public class LimitingResourceAllocationModel implements ILimitingResourceAllocat
             IOnTransaction<?> allocationDoer) {
         if (context != null) {
             org.zkoss.ganttz.data.Task ganttTask = context.getTask();
-            GanttDate previousStartDate = ganttTask.getBeginDate();
-            GanttDate previousEnd = ganttTask.getEndDate();
             transactionService.runOnReadOnlyTransaction(allocationDoer);
-            ganttTask.fireChangesForPreviousValues(previousStartDate,
-                    previousEnd);
+            ganttTask.enforceDependenciesDueToPositionPotentiallyModified();
         } else {
             // Update hours of a Task from Limiting Resource view
             transactionService.runOnReadOnlyTransaction(allocationDoer);
diff --git a/libreplan-webapp/src/main/java/org/libreplan/web/planner/order/SubcontractModel.java b/libreplan-webapp/src/main/java/org/libreplan/web/planner/order/SubcontractModel.java
index 23ea42245..8fb86529e 100644
--- a/libreplan-webapp/src/main/java/org/libreplan/web/planner/order/SubcontractModel.java
+++ b/libreplan-webapp/src/main/java/org/libreplan/web/planner/order/SubcontractModel.java
@@ -115,13 +115,10 @@ public class SubcontractModel implements ISubcontractModel {
     }
 
     private void recalculateTaskLength() {
-        GanttDate previousStartDate = ganttTask.getBeginDate();
-        GanttDate previousEnd = ganttTask.getEndDate();
-
         task.setStartDate(startDate);
         task.setEndDate(endDate);
 
-        ganttTask.fireChangesForPreviousValues(previousStartDate, previousEnd);
+        ganttTask.enforceDependenciesDueToPositionPotentiallyModified();
     }
 
     @Override
diff --git a/libreplan-webapp/src/main/java/org/libreplan/web/planner/reassign/ReassignCommand.java b/libreplan-webapp/src/main/java/org/libreplan/web/planner/reassign/ReassignCommand.java
index 937050874..9848e7af8 100644
--- a/libreplan-webapp/src/main/java/org/libreplan/web/planner/reassign/ReassignCommand.java
+++ b/libreplan-webapp/src/main/java/org/libreplan/web/planner/reassign/ReassignCommand.java
@@ -167,15 +167,11 @@ public class ReassignCommand implements IReassignCommand {
                 final int total = reassignations.size();
                 for (final WithAssociatedEntity each : reassignations) {
                     Task ganttTask = each.ganntTask;
-                    final GanttDate previousBeginDate = ganttTask
-                            .getBeginDate();
-                    final GanttDate previousEnd = ganttTask.getEndDate();
 
                     transactionService
                             .runOnReadOnlyTransaction(reassignmentTransaction(each));
                     diagramGraph.enforceRestrictions(each.ganntTask);
-                    ganttTask.fireChangesForPreviousValues(previousBeginDate,
-                            previousEnd);
+                    ganttTask.enforceDependenciesDueToPositionPotentiallyModified();
                     updater.doUpdate(showCompleted(i, total));
                     i++;
                 }