jQuery was never good at this. When I first used it on a project they had already drooped support for Safari 1.x, despite that being available version of Safari available for Mac OS X 10.4.
I was, at the time, living with my girlfriend and a friend of hers, both of whom used 10.4 and Safari 1.x: it was honestly quite common among people who couldn't quite afford new computers.
Regardless, when we sent the demo of our product for the local school district I was getting reports that the entire browser was crashing, which I traced down to some sketchy code in jQuery that had been tested so poorly on this version of Safari that no one noticed this highly fatal error.
When I reported the issue to a major jQuery contributor (a friend of mine), all I got was flak that people shouldn't be using that browser and should upgrade to 10.5... obviously I have never used jQuery in a project again.