Index: /applications/editors/josm/plugins/splinex/src/org/openstreetmap/josm/plugins/Splinex/Spline.java
===================================================================
--- /applications/editors/josm/plugins/splinex/src/org/openstreetmap/josm/plugins/Splinex/Spline.java	(revision 33554)
+++ /applications/editors/josm/plugins/splinex/src/org/openstreetmap/josm/plugins/Splinex/Spline.java	(revision 33555)
@@ -314,5 +314,5 @@
             nodes.add(idx, sn);
             if (!existing) {
-                getLayer().data.addPrimitive(sn.node);
+                getAffectedDataSet().addPrimitive(sn.node);
                 sn.node.setModified(true);
                 affected = true;
@@ -324,5 +324,5 @@
         public void undoCommand() {
             if (!existing)
-                getLayer().data.removePrimitive(sn.node);
+                getAffectedDataSet().removePrimitive(sn.node);
             nodes.remove(idx);
             affected = false;