Have you wondered why no one has answered your post?  It's because you haven't given anyone the ability to help you.  Did you write this code in a VB.NET app for Excel?  I ask that stupid question because you didn't give anyone the place you have this code.  What existing code module did you add it to?  Do you have it in a custom module?  All this would really be helpful in getting answers from the community.

The trick I use for these kind of situations is this: (house menu)
Set house menu to display page icons
For the link in the menu set (I take 30 px as an example):
a {height:30px; overflow:hidden}
Create one image, 60 pixels high that contains the normal image on the top and the "down image" on the bottom half.
(Hope this is clear)
Then set this image as the page icon and on
a:hover {margin-top: -30px;}
It will move the image up to show the bottom half of the image
You could even create a selected state this way if you would make a 90 pixels high image.
Hope this somehow solves your problem

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