html gifs disappear occasionally

[newhere]

Hi,

I have a frontend with dhtml,css and javascripts. Browser is IE6.Page
has a lot of div's .There are + and - gifs to hide and display
contents. When the page is first loaded everything works fine. After
toggling between hide and display gif for some time ,occasionally the
gif will disappear. The link will remain so you can toggle back but
the gif wont be visible. Once you toggle back the gif
reappears.Viewsource shows the exact source code when the gif is
visible or not. Not sure what the problem is . Any help would be
appreciated.

Thanks