The $(window).error() event/method doesn't pass the documented arguments correctly.

http://docs.jquery.com/Events/error#fn

A normal event gets one object, which is the event on most browsers (except IE which has a global event object). The window.onerror hander is defined to get THREE arguments: message, url, line number. Returning

true

prevents the default browser error dialog from being displayed. This is the opposite of a normal event where returning

false

prevents the default action.

In the test case attached, Firefox does call the jQuery handler but it gets only an incorrect event object. IE doesn't seem to call the jQuery handler.

A few possible solutions: 1) Drop support for the error event and have people use the native window.onerror. 2) Support the event as the native handler is documented, with three arguments and returning true to avoid a browser dialog. 3) Support the event but pass a special event object with properties similar to IE's and return false to avoid a browser dialog.