Opera 9.5 (at least this version) doesn't like null username being sent into XMLHttpRequest, this creates a login prompt in Opera, so jQuery should circumvent this

[kai@…]

By doing like this

if(s.username == null) { xml.open(s.type,s.url,s.async/*,s.username,s.password*/); } else { xml.open(s.type,s.url,s.async,s.username,s.password); }

The bug happens when you run getJSON or getScript with Opera 9.5, on a non password protected machine. In the IIS log I see the username "undefined" appear.

[flesler]

Fixed at [5604].

[kai@…]

actually this seems fixed in 1.2.4 according to the release notes, but I checked, and this fix is NOT included in 1.2.4.