Windows Safari 5 bug workaround: Backspace key in Silverlight

change

<param name="windowless" value="false">

to

<param name="windowless" value="true">

http://stackoverflow.com/questions/5110761/backspace-key-in-silverlight-text-box-shows-previous-page-in-safari-instead-of-ed

same in flash: http://stackoverflow.com/questions/3634822/windows-safari-5-bug-when-using-backspace-in-a-flash-web-application