diff --git a/smack-bosh/src/main/java/org/jivesoftware/smack/bosh/XMPPBOSHConnection.java b/smack-bosh/src/main/java/org/jivesoftware/smack/bosh/XMPPBOSHConnection.java
index db20c06f2..d59c46643 100644
--- a/smack-bosh/src/main/java/org/jivesoftware/smack/bosh/XMPPBOSHConnection.java
+++ b/smack-bosh/src/main/java/org/jivesoftware/smack/bosh/XMPPBOSHConnection.java
@@ -223,11 +223,8 @@ public class XMPPBOSHConnection extends AbstractXMPPConnection {
     }
 
     @Override
-    protected void loginNonAnonymously()
+    protected void loginNonAnonymously(String username, String password, String resource)
             throws XMPPException, SmackException, IOException {
-        String password = config.getPassword();
-        String resource = config.getResource();
-        String username = config.getUsername();
         if (saslAuthentication.hasNonAnonymousAuthentication()) {
             // Authenticate using SASL
             if (password != null) {
diff --git a/smack-core/src/main/java/org/jivesoftware/smack/AbstractXMPPConnection.java b/smack-core/src/main/java/org/jivesoftware/smack/AbstractXMPPConnection.java
index 1fe7bafef..c06ad1436 100644
--- a/smack-core/src/main/java/org/jivesoftware/smack/AbstractXMPPConnection.java
+++ b/smack-core/src/main/java/org/jivesoftware/smack/AbstractXMPPConnection.java
@@ -73,6 +73,7 @@ import org.jivesoftware.smack.provider.ProviderManager;
 import org.jivesoftware.smack.rosterstore.RosterStore;
 import org.jivesoftware.smack.util.DNSUtil;
 import org.jivesoftware.smack.util.PacketParserUtils;
+import org.jivesoftware.smack.util.StringUtils;
 import org.jivesoftware.smack.util.dns.HostAddress;
 import org.jxmpp.util.XmppStringUtils;
 import org.xmlpull.v1.XmlPullParser;
@@ -359,6 +360,8 @@ public abstract class AbstractXMPPConnection implements XMPPConnection {
      */
     protected abstract void connectInternal() throws SmackException, IOException, XMPPException;
 
+    private String usedUsername, usedPassword, usedResource;
+
     /**
      * Logs in to the server using the strongest authentication mode supported by
      * the server, then sets presence to available. If the server supports SASL authentication 
@@ -388,11 +391,56 @@ public abstract class AbstractXMPPConnection implements XMPPConnection {
         if (isAnonymous()) {
             loginAnonymously();
         } else {
-            loginNonAnonymously();
+            // The previously used username, password and resource take over precedence over the
+            // ones from the connection configuration
+            String username = usedUsername != null ? usedUsername : config.getUsername();
+            String password = usedPassword != null ? usedPassword : config.getPassword();
+            String resource = usedResource != null ? usedResource : config.getResource();
+            login(username, password, resource);
         }
     }
 
-    protected abstract void loginNonAnonymously() throws XMPPException, SmackException, IOException;
+    /**
+     * Same as {@link #login(String, String, String)}, but takes the resource from the connection
+     * configuration.
+     * 
+     * @param username
+     * @param password
+     * @throws XMPPException
+     * @throws SmackException
+     * @throws IOException
+     * @see #login
+     */
+    public void login(String username, String password) throws XMPPException, SmackException,
+                    IOException {
+        login(username, password, config.getResource());
+    }
+
+    /**
+     * Login with the given username. You may omit the password if a callback handler is used. If
+     * resource is null, then the server will generate one.
+     * 
+     * @param username
+     * @param password
+     * @param resource
+     * @throws XMPPException
+     * @throws SmackException
+     * @throws IOException
+     * @see #login
+     */
+    public void login(String username, String password, String resource) throws XMPPException,
+                    SmackException, IOException {
+        if (StringUtils.isNullOrEmpty(username)) {
+            throw new IllegalArgumentException("Username must not be null or empty");
+        }
+        usedUsername = username;
+        usedPassword = password;
+        usedResource = resource;
+        loginNonAnonymously(username, password, resource);
+    }
+
+    protected abstract void loginNonAnonymously(String username, String password, String resource)
+                    throws XMPPException, SmackException, IOException;
 
     protected abstract void loginAnonymously() throws XMPPException, SmackException, IOException;
 
@@ -471,8 +519,8 @@ public abstract class AbstractXMPPConnection implements XMPPConnection {
     }
 
     @Override
-    public boolean isAnonymous() {
-        return config.isAnonymous();
+    public final boolean isAnonymous() {
+        return config.getUsername() == null && usedUsername == null;
     }
 
     private String serviceName;
diff --git a/smack-core/src/main/java/org/jivesoftware/smack/ConnectionConfiguration.java b/smack-core/src/main/java/org/jivesoftware/smack/ConnectionConfiguration.java
index 4745f2751..6790bc4bc 100644
--- a/smack-core/src/main/java/org/jivesoftware/smack/ConnectionConfiguration.java
+++ b/smack-core/src/main/java/org/jivesoftware/smack/ConnectionConfiguration.java
@@ -102,10 +102,6 @@ public abstract class ConnectionConfiguration {
         }
         password = builder.password;
         callbackHandler = builder.callbackHandler;
-        if (callbackHandler == null && (password == null || username == null) && !builder.anonymous) {
-            throw new IllegalArgumentException(
-                            "Must provide either a username and password, a callback handler or set the connection configuration anonymous");
-        }
 
         // Resource can be null, this means that the server must provide one
         resource = builder.resource;
@@ -142,10 +138,6 @@ public abstract class ConnectionConfiguration {
         debuggerEnabled = builder.debuggerEnabled;
     }
 
-    public boolean isAnonymous() {
-        return username == null && callbackHandler == null;
-    }
-
     /**
      * Returns the server name of the target server.
      *
@@ -401,7 +393,6 @@ public abstract class ConnectionConfiguration {
         private HostnameVerifier hostnameVerifier;
         private String username;
         private String password;
-        private boolean anonymous;
         private String resource = "Smack";
         private boolean sendPresence = true;
         private boolean rosterLoadedAtLogin = true;
@@ -421,8 +412,7 @@ public abstract class ConnectionConfiguration {
         /**
          * Set the XMPP entities username and password.
          * <p>
-         * The username is the localpart of the entities JID, e.g. <code>localpart@example.org</code>. In order to
-         * create an anonymous connection, call {@link #makeAnonymous} instead.
+         * The username is the localpart of the entities JID, e.g. <code>localpart@example.org</code>.
          * </p>
          *
          * @param username
@@ -435,22 +425,6 @@ public abstract class ConnectionConfiguration {
             return getThis();
         }
 
-        /**
-         * Create a configuration for a anonymous XMPP connection.
-         * <p>
-         * Anonyous connections don't provide a username or other authentification credentials like a password. Instead
-         * the XMPP server, if supporting anonymous connections, will assign a username to the client.
-         * </p>
-         *
-         * @return a reference to this builder.
-         */
-        public B makeAnonymous() {
-            this.username = null;
-            this.password = null;
-            anonymous = true;
-            return getThis();
-        }
-
         /**
          * Set the service name of this XMPP service (i.e., the XMPP domain).
          *
diff --git a/smack-core/src/test/java/org/jivesoftware/smack/DummyConnection.java b/smack-core/src/test/java/org/jivesoftware/smack/DummyConnection.java
index 2a5235d71..8a8503b30 100644
--- a/smack-core/src/test/java/org/jivesoftware/smack/DummyConnection.java
+++ b/smack-core/src/test/java/org/jivesoftware/smack/DummyConnection.java
@@ -45,7 +45,6 @@ import org.jivesoftware.smack.packet.TopLevelStreamElement;
  */
 public class DummyConnection extends AbstractXMPPConnection {
 
-    private boolean anonymous = false;
     private boolean reconnect = false;
 
     private String connectionID;
@@ -93,7 +92,6 @@ public class DummyConnection extends AbstractXMPPConnection {
         connectionID = null;
         roster = null;
         authenticated = false;
-        anonymous = false;
         
         for (ConnectionListener listener : getConnectionListeners()) {
             listener.connectionClosed();
@@ -123,11 +121,6 @@ public class DummyConnection extends AbstractXMPPConnection {
         return roster;
     }
 
-    @Override
-    public boolean isAnonymous() {
-        return anonymous;
-    }
-
     @Override
     public boolean isSecureConnection() {
         return false;
@@ -139,15 +132,14 @@ public class DummyConnection extends AbstractXMPPConnection {
     }
 
     @Override
-    protected void loginNonAnonymously()
+    protected void loginNonAnonymously(String username, String password, String resource)
             throws XMPPException {
-        user = config.getUsername()
+        user = username
                 + "@"
                 + config.getServiceName()
                 + "/" 
-                + (config.getResource() != null ? config.getResource() : "Test");
+                + (resource != null ? resource : "Test");
         roster = new Roster(this);
-        anonymous = false;
         authenticated = true;
     }
 
@@ -159,7 +151,6 @@ public class DummyConnection extends AbstractXMPPConnection {
         if (isAuthenticated()) {
             throw new IllegalStateException("Already logged in to server.");
         }
-        anonymous = true;
         authenticated = true;
     }
 
diff --git a/smack-tcp/src/main/java/org/jivesoftware/smack/tcp/XMPPTCPConnection.java b/smack-tcp/src/main/java/org/jivesoftware/smack/tcp/XMPPTCPConnection.java
index a51c6997e..d37af04e9 100644
--- a/smack-tcp/src/main/java/org/jivesoftware/smack/tcp/XMPPTCPConnection.java
+++ b/smack-tcp/src/main/java/org/jivesoftware/smack/tcp/XMPPTCPConnection.java
@@ -339,10 +339,7 @@ public class XMPPTCPConnection extends AbstractXMPPConnection {
     }
 
     @Override
-    protected synchronized void loginNonAnonymously() throws XMPPException, SmackException, IOException {
-        String password = config.getPassword();
-        String resource = config.getResource();
-        String username = config.getUsername();
+    protected synchronized void loginNonAnonymously(String username, String password, String resource) throws XMPPException, SmackException, IOException {
         if (saslAuthentication.hasNonAnonymousAuthentication()) {
             // Authenticate using SASL
             if (password != null) {