I dont think you will be able to read a Max 9 file in Max 8.
You should maybe consider exchanging the files in either the collada or fbx format.
Nope, I don't know why, but Autodesk decided that you cannot open up files made on newer versions of Max with older versions of Max. So if I made a file on my sparkling nice 3DSMax 2010, you won't be able to open it on your dusty brown 3DS Max 8 or 9, or even 2008 or 2009. Even though there's like, BARELY any difference between the versions, you can't do it. (The same problem forced me to create my animations and models only at the campus for a while)