I spent quite a while scratching my head about how to read operational attributes such as create and modify timestamps.
This function solved it....
function get_entry_system_attrs( $ds, $dn, $deref=LDAP_DEREF_NEVER )
{
   $conn = $ds;
   $attrs = array( 'creatorsname', 'createtimestamp', 'modifiersname',
         'structuralObjectClass', 'entryUUID',  'modifytimestamp',
         'subschemaSubentry', 'hasSubordinates', '+' );
   $search = @ldap_read( $conn, $dn, '(objectClass=*)', $attrs, 0, 0, 0, $deref );
   if( ! $search )
      return false;
   $entry = ldap_first_entry( $conn, $search );
   if( ! $entry)
       return false;
   $attrs = ldap_get_attributes( $conn, $entry );
   if( ! $attrs )
      return false;
   if( ! isset( $attrs['count'] ) )
      return false;
   $count = $attrs['count'];
   unset( $attrs['count'] );
   $return_attrs = array();
   for( $i=0; $i<$count; $i++ ) {
      $attr_name = $attrs[$i];
      unset( $attrs[$attr_name]['count'] );
      $return_attrs[$attr_name] = $attrs[$attr_name];
   }
   return $return_attrs;
}