Hi Sharu,

Even i am looking for the same. Please if u find some solution, can u let me know.

Thanks

In my practise, had rewrited the topnav.jspf. When you can read the node data from the SPI model,and use the style (js and CSS),can implement it. The idea is that read the node data and level relationship from the SPI model, once you have got the data on the page you can custom the display style.
When you can read the first level nodes,you can reveal them by your mind.Then you get all children nodes of every nodes of first level of the page, so,when u click the certain node of first level, it can reveal all children nodes on the drop menu. I just had read the nodes data by coded, and can not custom the reveal style.

Enough is never enough