Normally, one can use javascript to close a window as long as the window was opened by following a link. But in Safari (and all WebKit versions to date) this fails after a get or post operation that targets an iframe within the window. Note that this is an important operation, as it would be used in an image upload window, for instance, where the post through the hidden iframe is used to submit an image. This same operation succeeds in FireFox, IE6, and IE7. Attached is a simple html file page that will allow you to reproduce the issue.
Created attachment 14162 [details] Page that demonstrates the bug.
If you there is a workaround for this bug, I'd love to hear about it.
I can no longer replicate this bug, and presume it to be fixed.
Still valid as of webkit-1.1.15.1 (as tested with midori-0.1.10 or the perl Gtk2-WebKit binding). Probably related to bug #16401