diff --git a/hudson/src/org/netbeans/modules/hudson/ui/wizard/InstanceDialog.java b/hudson/src/org/netbeans/modules/hudson/ui/wizard/InstanceDialog.java
--- a/hudson/src/org/netbeans/modules/hudson/ui/wizard/InstanceDialog.java
+++ b/hudson/src/org/netbeans/modules/hudson/ui/wizard/InstanceDialog.java
@@ -51,6 +51,7 @@
 import java.io.IOException;
 import java.net.HttpURLConnection;
 import java.net.URL;
+import java.net.URLConnection;
 import java.util.logging.Level;
 import java.util.logging.Logger;
 import javax.swing.JButton;
@@ -60,9 +61,11 @@
 import org.netbeans.modules.hudson.api.UI;
 import org.netbeans.modules.hudson.impl.HudsonInstanceImpl;
 import org.netbeans.modules.hudson.api.Utilities;
+import org.netbeans.modules.hudson.spi.ConnectionAuthenticator;
 import org.openide.DialogDescriptor;
 import org.openide.DialogDisplayer;
 import org.openide.NotifyDescriptor;
+import org.openide.util.Lookup;
 import org.openide.util.NbBundle;
 import org.openide.util.RequestProcessor;
 
@@ -108,6 +111,15 @@
                 try {
                     URL u = new URL(panel.getUrl());
                     HttpURLConnection connection = new ConnectionBuilder().homeURL(u).url(new URL(u, "?checking=redirects")).httpConnection(); // NOI18N
+                    for (ConnectionAuthenticator authenticator : Lookup.getDefault().lookupAll(ConnectionAuthenticator.class)) { // XXX conditionally!
+                        URLConnection retry = authenticator.forbidden(connection, u);
+                        if (retry != null) {
+                            connection = (HttpURLConnection) retry;
+                            authenticator.prepareRequest(retry, u);
+                            break;
+                        }
+                    }
+                    /*
                     String sVersion = connection.getHeaderField("X-Hudson"); // NOI18N
                     connection.disconnect();
                     if (sVersion == null) {
@@ -123,6 +135,7 @@
                         problem(NbBundle.getMessage(InstanceDialog.class, "MSG_incorrect_redirects"));
                         return;
                     }
+                    */
                 } catch (IOException x) {
                     LOG.log(Level.INFO, null, x);
                     problem(NbBundle.getMessage(InstanceDialog.class, "MSG_FailedToConnect"));