Index: /applications/viewer/jmapviewer/src/org/openstreetmap/gui/jmapviewer/OsmFileCacheTileLoader.java
===================================================================
--- /applications/viewer/jmapviewer/src/org/openstreetmap/gui/jmapviewer/OsmFileCacheTileLoader.java	(revision 13035)
+++ /applications/viewer/jmapviewer/src/org/openstreetmap/gui/jmapviewer/OsmFileCacheTileLoader.java	(revision 13036)
@@ -252,4 +252,5 @@
             url = new URL(tile.getUrl());
             HttpURLConnection urlConn = (HttpURLConnection) url.openConnection();
+            prepareHttpUrlConnection(urlConn);
             urlConn.setRequestMethod("HEAD");
             urlConn.setReadTimeout(30000); // 30 seconds read timeout
@@ -267,4 +268,5 @@
             url = new URL(tile.getUrl());
             HttpURLConnection urlConn = (HttpURLConnection) url.openConnection();
+            prepareHttpUrlConnection(urlConn);
             urlConn.setRequestMethod("HEAD");
             urlConn.setReadTimeout(30000); // 30 seconds read timeout
Index: /applications/viewer/jmapviewer/src/org/openstreetmap/gui/jmapviewer/OsmTileLoader.java
===================================================================
--- /applications/viewer/jmapviewer/src/org/openstreetmap/gui/jmapviewer/OsmTileLoader.java	(revision 13035)
+++ /applications/viewer/jmapviewer/src/org/openstreetmap/gui/jmapviewer/OsmTileLoader.java	(revision 13036)
@@ -19,4 +19,11 @@
  */
 public class OsmTileLoader implements TileLoader {
+
+    /**
+     * Holds the used user agent used for HTTP requests. If this field is 
+     * <code>null</code>, the default Java user agent is used.
+     */
+    public static String USER_AGENT = null;
+    public static String ACCEPT = "text/html, image/png, image/jpeg, image/gif, */*";
 
     protected TileLoaderListener listener;
@@ -66,7 +73,13 @@
         url = new URL(tile.getUrl());
         HttpURLConnection urlConn = (HttpURLConnection) url.openConnection();
-        urlConn.setReadTimeout(30000); // 30 seconds read
-        // timeout
+        prepareHttpUrlConnection(urlConn);
+        urlConn.setReadTimeout(30000); // 30 seconds read timeout
         return urlConn;
+    }
+
+    protected void prepareHttpUrlConnection(HttpURLConnection urlConn) {
+        if (USER_AGENT != null)
+            urlConn.setRequestProperty("User-agent", USER_AGENT);
+        urlConn.setRequestProperty("Accept", ACCEPT);
     }