You're going to have to do at least some javascript with that. Any time you want to manipulate the current page without a complete reload, you're looking at using ajax. Fortunately, it isn't very complicated thanks to libs like jQuery. Depending on what you're after, it could be as simple as the following:

$.get(http://some.data.url, function(html) {
    $('#some_div').html(data);
});

Or, if the content of the tabs is not very large, it can be done using only CSS ;)
What of course means, that the content of main area of must be loaded at once for all tabs.

Cool, yeah I thought it would involve JS. TorchSK, I'd like to avoid loading it all because there is a lot of data/queries involved for each tab.

I've never worked with $.get, I guess I could do something like:

$.get(document.domain/route, function(html) {

The domain shouldn't be changing, it'd just be kinda cool lol. I guess document.domain need to wrap the first param in quotes, like ' " ' + document.domain + ' /route" ' ? I could probably just test that. It's Friday and I'm rambling. :)