It's not true, because it's quite convertible character. At least for IIS:
http://example.com/test.asp?q=%uFF1Cscript>alert("Hello")</script>
where test.asp is
<%=Request.QueryString("q")%>
launches javascript.
This does not work for me for IIS 6 and IE 7. What platform did you test?
Regards, Brian
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