Index: lams_common/src/java/org/lamsfoundation/lams/util/svg/SVGGenerator.java
===================================================================
diff -u -rfd4021ffc5abccf1f6c12d71df287702da3b9edd -r07e000ffd4772f1832cb87aba7b843a4e824a449
--- lams_common/src/java/org/lamsfoundation/lams/util/svg/SVGGenerator.java	(.../SVGGenerator.java)	(revision fd4021ffc5abccf1f6c12d71df287702da3b9edd)
+++ lams_common/src/java/org/lamsfoundation/lams/util/svg/SVGGenerator.java	(.../SVGGenerator.java)	(revision 07e000ffd4772f1832cb87aba7b843a4e824a449)
@@ -159,8 +159,9 @@
 	    Point2D fromIntersection = SVGTrigonometryUtils.getRectangleAndLineSegmentIntersection(fromActivity, toActivity);
 	    Point2D toIntersection = SVGTrigonometryUtils.getRectangleAndLineSegmentIntersection(toActivity, fromActivity);            
             
-            //skip optional sequence's childs
-            if (fromActivity.isOptionalSequenceActivityChild()) {
+            //skip optional sequence's childs and lines between overlapped activities
+            if (fromActivity.isOptionalSequenceActivityChild() 
+        	    || (fromIntersection == null) || (toIntersection == null)) {
         	continue;
             }