Problems using Tree - DBsimple!

Hi group I have the following code: ------------------------------------------------------------------ require_once 'Tree/Tree.php'; // setup a memory tree using nested sets $tree = Tree::setup('Memory_DBsimple', $db, array('table' => 'menu', 'order' => 'priority', 'columnNameMaps' => array('parentId' => 'parentId', 'name' => 'title'), 'whereAddOn' => '')); // read the data from the DB and build the tree internally $tree->setup(); $tree->varDump(); print_r($tree->data); ------------------------------------------------------------------ And the following db-structure: ------------------------------------------------------------------ CREATE TABLE menu ( id int(10) unsigned NOT NULL auto_increment, parentId int(10) unsigned default NULL, priority smallint(6) NOT NULL default '0', title varchar(255) NOT NULL default '', PRIMARY KEY (id), KEY pid (parentId) ) TYPE=MyISAM COMMENT='Tree based menu system'; # # Data dump for tabellen menu # INSERT INTO menu VALUES (1, 0, 0, 'Personal'); INSERT INTO menu VALUES (2, 1, 0, 'Study'); INSERT INTO menu VALUES (3, 1, 1, 'Guestbook'); ------------------------------------------------------------------ Unfortunately my use of the Tree class doesn't seem to work properly - I get the following output from the above-code: ------------------------------------------------------------------ Warning: Invalid argument supplied for foreach() in z:\php\pear\Tree\Memory.php on line 1276 Warning: Invalid argument supplied for foreach() in z:\php\pear\Tree\Memory.php on line 1284 Array ( [1] => Array ( [id] => 1 [priority] => 0 [name] => Personal [nextId] => 2 [next] => Array ( [id] => 2 [priority] => 0 [name] => Study [prevId] => 1 [previous] => Array *RECURSION* [nextId] => 3 [next] => Array ( [id] => 3 [priority] => 1 [name] => Guestbook [prevId] => 2 [previous] => Array *RECURSION* ) ) ) [2] => Array ( [id] => 2 [priority] => 0 [name] => Study [prevId] => 1 [previous] => Array ( [id] => 1 [priority] => 0 [name] => Personal [nextId] => 2 [next] => Array *RECURSION* ) [nextId] => 3 [next] => Array ( [id] => 3 [priority] => 1 [name] => Guestbook [prevId] => 2 [previous] => Array *RECURSION* ) ) [3] => Array ( [id] => 3 [priority] => 1 [name] => Guestbook [prevId] => 2 [previous] => Array ( [id] => 2 [priority] => 0 [name] => Study [prevId] => 1 [previous] => Array ( [id] => 1 [priority] => 0 [name] => Personal [nextId] => 2 [next] => Array *RECURSION* ) [nextId] => 3 [next] => Array *RECURSION* ) ) [] => ) ------------------------------------------------------------------ How come it doesn't work... :-/ - Apparently the records are read from the database but not processed correctly - any ideas? Hope you can help me out here! Cheers, Tommy Ipsen