Index: lams_common/src/java/org/lamsfoundation/lams/util/svg/ActivityTreeNodeComparator.java
===================================================================
diff -u
--- lams_common/src/java/org/lamsfoundation/lams/util/svg/ActivityTreeNodeComparator.java	(revision 0)
+++ lams_common/src/java/org/lamsfoundation/lams/util/svg/ActivityTreeNodeComparator.java	(revision 0b02d389a59265642e50850e05c5bc0319a5dcf2)
@@ -0,0 +1,62 @@
+/**************************************************************** 
+ * Copyright (C) 2005 LAMS Foundation (http://lamsfoundation.org) 
+ * ============================================================= 
+ * License Information: http://lamsfoundation.org/licensing/lams/2.0/ 
+ * 
+ * This program is free software; you can redistribute it and/or modify 
+ * it under the terms of the GNU General Public License version 2.0 
+ * as published by the Free Software Foundation. 
+ * 
+ * This program is distributed in the hope that it will be useful, 
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of 
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the 
+ * GNU General Public License for more details. 
+ * 
+ * You should have received a copy of the GNU General Public License 
+ * along with this program; if not, write to the Free Software 
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 * USA 
+ * 
+ * http://www.gnu.org/licenses/gpl.txt 
+ * **************************************************************** 
+ */  
+ 
+/* $Id$ */  
+package org.lamsfoundation.lams.util.svg;
+
+import java.io.Serializable;
+import java.util.Comparator;
+
+import org.lamsfoundation.lams.learningdesign.dto.AuthoringActivityDTO;
+
+/**
+ * The activity order comparator used for sorted set. Order id is used as
+ * the primary comparing criteria as it is unique within a complex activity.
+ * If they are the same, activity id are used for comparison to ensure the
+ * sorted set won't treat two activities with the same order id as the 
+ * same activity.
+ * 
+ * @author Andrey Balan
+ */
+public class ActivityTreeNodeComparator implements Comparator<ActivityTreeNode> {
+
+    /**
+     * Compare the order.
+     * @see java.util.Comparator#compare(java.lang.Object, java.lang.Object)
+     */
+    public int compare(ActivityTreeNode treeNode1, ActivityTreeNode treeNode2) {
+	AuthoringActivityDTO activity1 = treeNode1.getActivity();
+	AuthoringActivityDTO activity2 = treeNode2.getActivity();
+        
+        if(activity1.getOrderID()==null||activity2.getOrderID()==null)
+            return activity1.getActivityID().compareTo(activity2.getActivityID());
+        
+        int orderDiff = activity1.getOrderID().compareTo(activity2.getOrderID());
+        //return order id compare result if they are not the same
+        if(orderDiff!=0)
+            return orderDiff;
+        //if order id are the same, compare activity id.
+        else
+            return activity1.getActivityID().compareTo(activity2.getActivityID());
+    }
+    
+}
Index: lams_common/src/java/org/lamsfoundation/lams/util/svg/SVGGenerator.java
===================================================================
diff -u -r07e000ffd4772f1832cb87aba7b843a4e824a449 -r0b02d389a59265642e50850e05c5bc0319a5dcf2
--- lams_common/src/java/org/lamsfoundation/lams/util/svg/SVGGenerator.java	(.../SVGGenerator.java)	(revision 07e000ffd4772f1832cb87aba7b843a4e824a449)
+++ lams_common/src/java/org/lamsfoundation/lams/util/svg/SVGGenerator.java	(.../SVGGenerator.java)	(revision 0b02d389a59265642e50850e05c5bc0319a5dcf2)
@@ -29,11 +29,13 @@
 import java.util.ArrayList;
 import java.util.HashMap;
 import java.util.Iterator;
+import java.util.TreeSet;
 
 import org.apache.batik.dom.svg.SVGDOMImplementation;
 import org.apache.commons.lang.StringUtils;
 import org.jdom.JDOMException;
 import org.lamsfoundation.lams.learningdesign.Activity;
+import org.lamsfoundation.lams.learningdesign.ActivityDTOOrderComparator;
 import org.lamsfoundation.lams.learningdesign.dto.AuthoringActivityDTO;
 import org.lamsfoundation.lams.learningdesign.dto.LearningDesignDTO;
 import org.lamsfoundation.lams.learningdesign.dto.TransitionDTO;
@@ -369,7 +371,9 @@
 	    startingPoint.setAttributeNS(null, "style", "fill:#000000");
 	    g.appendChild(startingPoint);
 	    
-	    Iterator<ActivityTreeNode> sequenceNodeIterator = node.getChildren().iterator();
+	    TreeSet<ActivityTreeNode> sequenceNodes = new TreeSet<ActivityTreeNode>(new ActivityTreeNodeComparator());
+	    sequenceNodes.addAll(node.getChildren());
+	    Iterator<ActivityTreeNode> sequenceNodeIterator = sequenceNodes.iterator();
 	    for (int sequenceIndex = -1; sequenceNodeIterator.hasNext() && (sequenceIndex < 4); sequenceIndex++) {
 		ActivityTreeNode sequenceNode = sequenceNodeIterator.next();
 		double previousActivityPointX = startingPointX + BRANCHING_ACTIVITY_POINT/2;