Thank you David, i have added the loading of dojo.xd.js as below and it worked fine, but i have a query...
I download the dojo.xd.js file separately. I did not find in dojo 1.4 package download. Is there any such similar file in dojo1.4 ?
I have one more doubt, that while creating a Dojo tree, is there any mechanism to perform some operation or show some value in a content pane based on the selected node of the tree.