I\'m using Facebook Connect in my app. I have it working pretty well, but in the Safari Error console, I\'m seeing errors like this:
Unsafe JavaScript attemp
It means you're attempting some form of cross origin access, which is unsafe -- while it may seem benign it's probably worth trying to find out why you're hitting it, if you use the nightlies or the Safari4 beta you can use the debugger in the web inspector, and make it break on all exceptions, which will let you see when it's actually attempting the cross-origin access.
As for the hangs, if you can find some kind of reduced testcase it would be great if you could file them at http://bugs.webkit.org