Index: /trunk/src/org/openstreetmap/josm/gui/layer/imagery/TileCoordinateConverter.java
===================================================================
--- /trunk/src/org/openstreetmap/josm/gui/layer/imagery/TileCoordinateConverter.java	(revision 14504)
+++ /trunk/src/org/openstreetmap/josm/gui/layer/imagery/TileCoordinateConverter.java	(revision 14505)
@@ -22,4 +22,6 @@
 import org.openstreetmap.josm.gui.MapView;
 import org.openstreetmap.josm.gui.MapViewState.MapViewPoint;
+import org.openstreetmap.josm.tools.JosmRuntimeException;
+import org.openstreetmap.josm.tools.bugreport.BugReport;
 
 /**
@@ -80,6 +82,13 @@
      */
     public Point2D getPixelForTile(int x, int y, int zoom) {
-        ICoordinate coord = tileSource.tileXYToLatLon(x, y, zoom);
-        return pos(coord).getInView();
+        try {
+            ICoordinate coord = tileSource.tileXYToLatLon(x, y, zoom);
+            if (Double.isNaN(coord.getLat()) || Double.isNaN(coord.getLon())) {
+                throw new JosmRuntimeException("tileXYToLatLon returned " + coord);
+            }
+            return pos(coord).getInView();
+        } catch (RuntimeException e) {
+            throw BugReport.intercept(e).put("tileSource", tileSource).put("x", x).put("y", y).put("zoom", zoom);
+        }
     }