I don't want to sound like one of these luddite users who are making your life difficult, but looking at the site I think I can understand why they're upset. You seem to be causing a lot of trouble for older browsers in order to do that trick where you update part of the page without actually reloading. I can't see how this is worth it, when just going to a new URL with the content showing would work just as well. In fact you're breaking common features of every browser, like bookmarks and mailing URLs to people (there is no way to mail someone a link to your "alumni & friends" page, for example).
A text version of a site is always welcome, but the one you provide here isn't very useable. Why is this all on one page? Why isn't it split into multiple URLs? It may be a bit harder, but it would make much more sense.
Have you noticed that all of the most successful sites work in older browsers? These fancy so-called "DHTML" features just don't add that much value and they shut out some of your users. I don't think they're worth it.