Is there any definitive way to get the error to occur? I tried hitting the page from a couple different machines with every browser I have and can't the page to look any different than what I suspect is how it's supposed to display. If you can get the page to display incorrectly on your end, I'd recommend doing a View Source of the page and saving it off somewhere on your desktop, then viewing the page while it displays normally, doing a View Source, and saving that off as well. Then use something like WinMerge to compare the two files and see if there are any differences...the different browsers may just be rendering a specific piece of script or html differently.
<a href="http://www.aspdotnetstorefront.com">Shopping Cart Software</a>