Tooltip placement fails without 'www' in browser address

I have implemented the “simple tooltip” from chapter 5, item 17 of “Jquery Novice to Ninja”. It works beautifully when run on localhost, or on the live site with ‘www’ in the address.

But omitting ‘www.’ from the URL causes the javascript to run, but the tooltip does not get placed correctly.

See it here: http://www.buckspringsresort.com/specials.html

Try it with & without ‘www.’ The tool tip is attached to the “Green Company” link at the bottom right.

Am I missing something important?

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My bad: this seems to happen only in Firefox; I bet it’s an add-on causing the behavior, but it’s still kinda strange to me. Thanks…