I have noticed this bug when developing my flash application on a windows platform. If typing text in to a text box in a Flash swf running in Safari 5 browser on Windows then press backspace the browser will jump to the previous page in history rather than performing the function that backspace is supposed to - here is a link to another report of this apple bug -
http://www.ruelke.org/blog-entry-138.html
How can we work around this apple problem? cheers