diff --git a/navalplanner-webapp/src/main/java/org/navalplanner/web/planner/allocation/StretchesFunctionModel.java b/navalplanner-webapp/src/main/java/org/navalplanner/web/planner/allocation/StretchesFunctionModel.java
index 74fd9d68a..c61aa4462 100644
--- a/navalplanner-webapp/src/main/java/org/navalplanner/web/planner/allocation/StretchesFunctionModel.java
+++ b/navalplanner-webapp/src/main/java/org/navalplanner/web/planner/allocation/StretchesFunctionModel.java
@@ -31,6 +31,7 @@ import java.util.List;
 import org.joda.time.LocalDate;
 import org.navalplanner.business.calendars.entities.BaseCalendar;
 import org.navalplanner.business.common.exceptions.ValidationException;
+import org.navalplanner.business.planner.daos.IAssignmentFunctionDAO;
 import org.navalplanner.business.planner.daos.ITaskElementDAO;
 import org.navalplanner.business.planner.entities.AssignmentFunction;
 import org.navalplanner.business.planner.entities.Stretch;
@@ -75,10 +76,14 @@ public class StretchesFunctionModel implements IStretchesFunctionModel {
     @Autowired
     private ITaskElementDAO taskElementDAO;
 
+    @Autowired
+    private IAssignmentFunctionDAO assignmentFunctionDAO;
+
     @Override
     @Transactional(readOnly = true)
     public void init(StretchesFunction stretchesFunction, Task task) {
         if (stretchesFunction != null) {
+            assignmentFunctionDAO.reattach(stretchesFunction);
             this.originalStretchesFunction = stretchesFunction;
             this.stretchesFunction = copy(stretchesFunction);
 
diff --git a/navalplanner-webapp/src/main/java/org/navalplanner/web/planner/tabs/AdvancedAllocationTabCreator.java b/navalplanner-webapp/src/main/java/org/navalplanner/web/planner/tabs/AdvancedAllocationTabCreator.java
index 5923a91b3..2d2496bab 100644
--- a/navalplanner-webapp/src/main/java/org/navalplanner/web/planner/tabs/AdvancedAllocationTabCreator.java
+++ b/navalplanner-webapp/src/main/java/org/navalplanner/web/planner/tabs/AdvancedAllocationTabCreator.java
@@ -147,7 +147,7 @@ public class AdvancedAllocationTabCreator {
 
         private void reattachResources() {
             for (Resource each : associatedResources) {
-                resourceDAO.save(each);
+                resourceDAO.reattach(each);
             }
         }