diff --git a/ganttzk/src/main/java/org/zkoss/ganttz/DependencyComponent.java b/ganttzk/src/main/java/org/zkoss/ganttz/DependencyComponent.java
index c22f0696f..22f28859c 100644
--- a/ganttzk/src/main/java/org/zkoss/ganttz/DependencyComponent.java
+++ b/ganttzk/src/main/java/org/zkoss/ganttz/DependencyComponent.java
@@ -100,8 +100,8 @@ public class DependencyComponent extends XulElement implements AfterCompose {
     }
 
     public Dependency getDependency() {
-        return new Dependency(source.getTask(), destination
-                .getTask(), DependencyType.END_START);
+        return context.getDiagramGraph().getDependencyFrom(source.getTask(),
+                destination.getTask());
     }
 
     public DependencyType getDependencyType() {
diff --git a/ganttzk/src/main/java/org/zkoss/ganttz/FunctionalityExposedForExtensions.java b/ganttzk/src/main/java/org/zkoss/ganttz/FunctionalityExposedForExtensions.java
index 20e55ae00..6f750e7ec 100644
--- a/ganttzk/src/main/java/org/zkoss/ganttz/FunctionalityExposedForExtensions.java
+++ b/ganttzk/src/main/java/org/zkoss/ganttz/FunctionalityExposedForExtensions.java
@@ -243,15 +243,19 @@ public class FunctionalityExposedForExtensions<T> implements IContext<T> {
         return dep;
     }
 
-    public void addDependency(DependencyComponent dependencyComponent) {
-        Dependency dependency = dependencyComponent.getDependency();
+    public void addDependency(Dependency dependency) {
         if (!canAddDependency(dependency))
             return;
-        getDependencyList().addDependencyComponent(dependencyComponent);
         diagramGraph.add(dependency);
+        getDependencyList().addDependencyComponent(
+                getTaskList().asDependencyComponent(dependency));
         adapter.addDependency(toDomainDependency(dependency));
     }
 
+    private TaskList getTaskList() {
+        return planner.getTaskList();
+    }
+
     private boolean canAddDependency(Dependency dependency) {
         return adapter.canAddDependency(toDomainDependency(dependency));
     }
diff --git a/ganttzk/src/main/java/org/zkoss/ganttz/TaskList.java b/ganttzk/src/main/java/org/zkoss/ganttz/TaskList.java
index 746f2c0c1..8d34775a4 100644
--- a/ganttzk/src/main/java/org/zkoss/ganttz/TaskList.java
+++ b/ganttzk/src/main/java/org/zkoss/ganttz/TaskList.java
@@ -1,12 +1,14 @@
 package org.zkoss.ganttz;
 
 import java.util.ArrayList;
+import java.util.Arrays;
 import java.util.Collection;
 import java.util.HashMap;
 import java.util.List;
 import java.util.Map;
 
 import org.zkoss.ganttz.data.Dependency;
+import org.zkoss.ganttz.data.DependencyType;
 import org.zkoss.ganttz.data.Position;
 import org.zkoss.ganttz.data.Task;
 import org.zkoss.ganttz.util.MenuBuilder;
@@ -80,6 +82,10 @@ public class TaskList extends XulElement implements AfterCompose {
         return result;
     }
 
+    public DependencyComponent asDependencyComponent(Dependency dependency) {
+        return asDependencyComponents(Arrays.asList(dependency)).get(0);
+    }
+
     public synchronized void addTaskComponent(Component beforeThis,
             final TaskComponent taskComponent, boolean relocate) {
         final boolean isFirst = getFirstTopTaskComponent() == null
@@ -290,9 +296,7 @@ public class TaskList extends XulElement implements AfterCompose {
     }
 
     public void addDependency(TaskComponent source, TaskComponent destination) {
-        DependencyComponent dependencyComponent = new DependencyComponent(
-                context,
-                source, destination);
-        context.addDependency(dependencyComponent);
+        context.addDependency(new Dependency(source.getTask(), destination
+                .getTask(), DependencyType.END_START));
     }
 }
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 8541fa039..94f88f897 100644
--- a/ganttzk/src/main/java/org/zkoss/ganttz/data/GanttDiagramGraph.java
+++ b/ganttzk/src/main/java/org/zkoss/ganttz/data/GanttDiagramGraph.java
@@ -225,4 +225,8 @@ public class GanttDiagramGraph {
         parentShrinkingEnforcer.enforce();
     }
 
+    public Dependency getDependencyFrom(Task from, Task to) {
+        return graph.getEdge(from, to);
+    }
+
 }