Index: src/org/openstreetmap/josm/gui/layer/gpx/ConvertFromGpxLayerAction.java
===================================================================
--- src/org/openstreetmap/josm/gui/layer/gpx/ConvertFromGpxLayerAction.java	(Revision 14447)
+++ src/org/openstreetmap/josm/gui/layer/gpx/ConvertFromGpxLayerAction.java	(Arbeitskopie)
@@ -42,7 +42,6 @@
 public class ConvertFromGpxLayerAction extends ConvertToDataLayerAction<GpxLayer> {
 
     private static final String GPX_SETTING = "gpx.convert-tags";
-    private final DateFormat timeFormatter = DateUtils.getGpxFormat();
 
     /**
      * Creates a new {@code FromGpxLayer}.
@@ -82,7 +81,7 @@
                             // timestamps should always be converted
                             Date date = (Date) obj;
                             if (!none) { //... but the tag will only be set when required
-                                n.put(key, timeFormatter.format(date));
+                                n.put(key, DateUtils.fromDate(date));
                             }
                             n.setTimestamp(date);
                         }
Index: src/org/openstreetmap/josm/io/GpxWriter.java
===================================================================
--- src/org/openstreetmap/josm/io/GpxWriter.java	(Revision 14447)
+++ src/org/openstreetmap/josm/io/GpxWriter.java	(Arbeitskopie)
@@ -37,8 +37,6 @@
  */
 public class GpxWriter extends XmlWriter implements GpxConstants {
 
-    private final DateFormat gpxFormat = DateUtils.getGpxFormat();
-
     /**
      * Constructs a new {@code GpxWriter}.
      * @param out The output writer
@@ -120,7 +118,7 @@
                 } else {
                     Object val = obj.get(key);
                     if (val instanceof Date) {
-                        simpleTag(key, gpxFormat.format(val));
+                        simpleTag(key, DateUtils.fromDate((Date) val));
                     } else if (val instanceof Number) {
                         simpleTag(key, val.toString());
                     } else if (val != null) {