in the Dreamweaver tag selector, select the body tag.
in the behaviors panel, apply the Set Selected In List behavior to set the selected item in the parent list to the onload attribute of the body tag,
Then add the Populate list from array behavior to populate the child list, also to the onload attribute of the body tag
then add a second set selected in list behavior to set the selected item in the child list. again, this is applied to the unload attribute of the body tag.