autocomplete - Firefox, leaving cursor over result set while typing overwrites typed text

In Firefox (tested in 3.6.2).

Reproducible on jQuery UI autocomplete demo page:

http://jqueryui.com/demos/autocomplete/

Step 1) Give the autocomplete input focus.

Step 2) Move the cursor over to where an item in the autocomplete suggest will appear once the user starts entering text (usally just below the autocomplete input field)

Step 3) Start typing text in the autocomplete input box. The box will automatically fill with whatever item the cursor is floating over. For instance, on the demo page, typing "a" with the cursor left over where the first item appears, "java", will change the text in the input field to "java", regardless of whether or not the user actually the third item in the list "asp".

This does not occur in IE7 or Chrome.