Index: /trunk/src/org/openstreetmap/josm/gui/MainApplication.java
===================================================================
--- /trunk/src/org/openstreetmap/josm/gui/MainApplication.java	(revision 11454)
+++ /trunk/src/org/openstreetmap/josm/gui/MainApplication.java	(revision 11455)
@@ -12,7 +12,5 @@
 import java.net.Inet6Address;
 import java.net.InetAddress;
-import java.net.InetSocketAddress;
 import java.net.ProxySelector;
-import java.net.Socket;
 import java.net.URL;
 import java.security.AllPermission;
@@ -36,4 +34,5 @@
 import java.util.stream.Stream;
 
+import javax.net.ssl.SSLSocketFactory;
 import javax.swing.JOptionPane;
 import javax.swing.RepaintManager;
@@ -448,7 +447,5 @@
                             if (a.isReachable(1000)) {
                                 /* be sure it REALLY works */
-                                Socket s = new Socket();
-                                s.connect(new InetSocketAddress(a, 80), 1000);
-                                s.close();
+                                SSLSocketFactory.getDefault().createSocket(a, 443).close();
                                 Utils.updateSystemProperty("java.net.preferIPv6Addresses", "true");
                                 if (!wasv6) {