[horde] delete problem

[fixinko]

Hello,
i'm using horde 3.0 framework, imp h3 4.0 on apache 2.0.52, php5.0.3. 
When I check an email which I would to delete and click on the delete 
link,  php shows me this error *"Fatal error*: Call to undefined method 
DataTree_null::removeByNames() in 
*/var/www/htdocs/horde/lib/Horde/History.php* on line *290**";* but the 
email was marked as deleted.

Thanks.