diff --git a/ganttzk/src/main/java/org/zkoss/ganttz/TaskEditFormComposer.java b/ganttzk/src/main/java/org/zkoss/ganttz/TaskEditFormComposer.java
index 3c44e2844..fb098f174 100644
--- a/ganttzk/src/main/java/org/zkoss/ganttz/TaskEditFormComposer.java
+++ b/ganttzk/src/main/java/org/zkoss/ganttz/TaskEditFormComposer.java
@@ -29,7 +29,7 @@ import org.zkoss.zk.ui.event.Event;
 import org.zkoss.zk.ui.util.GenericForwardComposer;
 import org.zkoss.zul.Datebox;
 import org.zkoss.zul.Textbox;
-import org.zkoss.zul.api.Popup;
+import org.zkoss.zul.api.Window;
 
 public class TaskEditFormComposer extends GenericForwardComposer {
 
@@ -37,7 +37,7 @@ public class TaskEditFormComposer extends GenericForwardComposer {
 
     }
 
-    private Popup popUp;
+    private Window popUp;
 
     private Task currentTask;
 
@@ -52,18 +52,21 @@ public class TaskEditFormComposer extends GenericForwardComposer {
     @Override
     public void doAfterCompose(Component comp) throws Exception {
         super.doAfterCompose(comp);
-        popUp = (Popup) comp;
+        popUp = (Window) comp;
     }
 
     public void showEditFormFor(Component openRelativeTo, Task task) {
         this.currentTask = task;
-        popUp.open(openRelativeTo, "after_start");
+        try {
+            popUp.setMode("modal");
+        } catch (InterruptedException e) {
+            throw new RuntimeException(e);
+        }
         updateComponentValuesForTask(currentTask);
     }
 
     private void updateComponentValuesForTask(
             ITaskFundamentalProperties currentTask) {
-        // popUp.setTitle(currentTask.getName());
         name.setValue(currentTask.getName());
         startDateBox.setValue(currentTask.getBeginDate());
         endDateBox.setValue(new Date(currentTask.getBeginDate().getTime()
@@ -90,7 +93,7 @@ public class TaskEditFormComposer extends GenericForwardComposer {
 
     public void onClick$ok(Event event) {
         if (okPressed()) {
-            popUp.close();
+            popUp.setVisible(false);
         }
     }
 
@@ -102,4 +105,4 @@ public class TaskEditFormComposer extends GenericForwardComposer {
         return true;
     }
 
-}
+}
\ No newline at end of file
diff --git a/navalplanner-webapp/src/main/webapp/planner/order.zul b/navalplanner-webapp/src/main/webapp/planner/order.zul
index 18a7f6aaf..f0e6fd1e8 100644
--- a/navalplanner-webapp/src/main/webapp/planner/order.zul
+++ b/navalplanner-webapp/src/main/webapp/planner/order.zul
@@ -40,7 +40,11 @@
         </planner>
     </div>
 
-    <popup width="300px" apply="${planningController.editTaskController}">
+    <window id="taskPropertiesWindow"
+        apply="${planningController.editTaskController}" closable="true"
+        title="${i18n:_('Task properties')}" width="650px" visible="false"
+        border="normal">
+
         <grid>
             <rows>
                 <row>
@@ -79,7 +83,7 @@
             </rows>
         </grid>
         <button id="ok" label="${i18n:_('Accept')}" />
-    </popup>
+    </window>
 
     <window id="resourceAllocationWindow"
         apply="${allocationController}" closable="true"