Yes this is possible in DHTML. If I understand your question correctly, the following code will do what you want it to do. However, please note that you will have to provide a browser detect script to insure that you can display layers in the visitors browser.
Hope this helps
- Q2
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Untitled Document
Menu
Click on the word "Menu" to show the drop down.
Move your mouse off the drop down to make it disappear.
-Q2