How to Make a Multi-Selection List Box Position at First Selection After Postback

VWD 2008 Express.  Visual Basic.

I have a list box with SelectionMode=Multiple.  Thus, a user can select one or more items from the list box. After the user has selected item(s) from the list and a postback occurs, the list box goes back to the top.  Hence, if the selection is a ways down the list, the user can no longer see that it is selected (although if the user scrolls down in the list box they will see the item(s) still selected).

How can I make the list box to return to for instance the first selected item after a postback?  Incidentally, this problem does not occur if the SelectionMode=Single.  Thanks for the help.
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