Index: Ldap.php
===================================================================
--- Ldap.php	(revision 9105)
+++ Ldap.php	(working copy)
@@ -630,8 +630,11 @@
             $password = $this->_getPassword();
             $moreCreds = false;
         }
+		
+		if ($username===null && $password===null) $bindAnonymously=true;
+		else $bindAnonymously=false;
 
-        if (!$username) {
+        if (!$bindAnonymously && !$username) {
             /**
              * @see Zend_Ldap_Exception
              */
@@ -641,7 +644,7 @@
 
         /* Check to make sure the username is in DN form.
          */
-        if (!Zend_Ldap::explodeDn($username)) {
+        if (!$bindAnonymously && !Zend_Ldap::explodeDn($username)) {
             if ($this->_options['bindRequiresDn']) {
                 /* moreCreds stops an infinite loop if _getUsername does not
                  * return a DN and the bind requires it
@@ -685,7 +688,7 @@
         if (@ldap_bind($this->_resource, $username, $password))
             return $this;
 
-        $message = $username;
+        $message = ($bindAnonymously) ? "anonymous bind" : $username;
 
         /**
          * @see Zend_Ldap_Exception