How to use interfaces from IE9 Beta library?

I asked similar question at Internet Explorer Extens开发者_开发技巧ion Development Forum but didn't get the answer. I found that not only me has this problem

Did anyone used any of these interfaces from IE9 Beta? I'm querying for IHTMLDocument7 using ATL but I get NULL pointer

CComQIPtr<IHTMLDocument7> document7 = document3;
if(document7)
{
//do sth with document7
}

but document7 is NULL. Other interfaces (IHTMLDocument1-6) works fine.