Index: trunk/src/org/openstreetmap/josm/io/session/ImagerySessionExporter.java
===================================================================
--- trunk/src/org/openstreetmap/josm/io/session/ImagerySessionExporter.java	(revision 8802)
+++ trunk/src/org/openstreetmap/josm/io/session/ImagerySessionExporter.java	(revision 8803)
@@ -88,4 +88,6 @@
             data.put("show-errors", Boolean.toString(tsLayer.showErrors));
         }
+        data.put("dx", String.valueOf(layer.getDx()));
+        data.put("dy", String.valueOf(layer.getDy()));
         for (Map.Entry<String, String> entry : data.entrySet()) {
             Element attrElem = support.createElement(entry.getKey());
Index: trunk/src/org/openstreetmap/josm/io/session/ImagerySessionImporter.java
===================================================================
--- trunk/src/org/openstreetmap/josm/io/session/ImagerySessionImporter.java	(revision 8802)
+++ trunk/src/org/openstreetmap/josm/io/session/ImagerySessionImporter.java	(revision 8803)
@@ -60,4 +60,7 @@
             }
         }
+        if (attributes.containsKey("dx") && attributes.containsKey("dy")) {
+            layer.setOffset(Double.parseDouble(attributes.get("dx")), Double.parseDouble(attributes.get("dy")));
+        }
         return layer;
     }