AJAX and Basename

AJAX and Basename

I posted a question recently, to no avail, trying to determine why $.ajax would work on any browser on a PC, but no browser on a Mac. Today, I discovered that $.ajax will work on a Mac if you type the url as 'http://www.domain.com' rather than 'http://domain.com'. To be clear, I have a local server set up under 'domain.com' (rather 'https://mail.domain.com' for remote email service), but the web server is at 'www.domain.com'.

Can someone explain this to me?

I know I can fix the issue on the server itself, but I am curious as to why a PC, regardless of the browser, will process and load information using $.ajax but a Mac, again browser-independent, will not.

For clarification, my Mac will actually process $.ajax and return a success, but it will not load the new data (I get a blank div).

Any ideas or explanations will be greatly appreciated.