Problem with having more number of nodes

i have a tree with more than 2000 nodes. my criteria is when i check a parent it should check all the children including grand children.
i am using openItem(nodeid) method but it is not opening all the nodes. it is skipping some of the nodes.
this problem occurs only when i have more number of nodes.
How to resolve this


Are you using dynamic loading of sub items? In such case you can should additional Ajax request to the server side and check checkboxes on the server side.