IE CSS hover image not clearing after hover

[Vigothe6th]

I have a problem with the site I am designing. Internet explorer when you move your mouse over the button from the top the hover works correctly, when you move the mouse from bottom to top the image does not disapear like it should until you move from top down again.
The page is http://www.cobratec.com/navtest.html


Sorry for the sloppiness of my code, I've been trying alot of things to fix the problem and may have some unneeded bits there.

In addition to that problem I just discovered that the page is displaying differently on different computers all using IE 6.

In versions
6.0.29D0.2180.xpsp.050928-1517
6.0.2900.2180.xpsp_sp2_rtm.040803-2158
the page only has the problem I listed above.
But in IE version
6.0.2900.2180.xpsp_sp2_gdr.050301-1519
it has the problem listed above and the buttons flicker when you hover over them and sometimes disapear completely.
Does anyone know what I can do to fix these problems?

[scoutt]

I would say you have issues in your code. cause once you hover over them they are done, it is like they are not getting set back to the default. doesn't matter which ay you go, up down left or right. I would look at it but you have it as a htc file. I don't do those files.