页面后退问题

http://msdn.microsoft.com/workshop/author/persistence/overview.asp<HTML>
<HEAD>
<META NAME="save" CONTENT="history">
<STYLE>
   .sHistory {behavior:url(#default#savehistory);}
</STYLE>
</HEAD>
<BODY>
<INPUT class=sHistory type=text id=oPersistInput>
</BODY>
</HTML>