The links only help those of us who have accounts on metalink, which is only available to people who know their company's support contract info with Oracle. (and I don't currently work for a company with a CSI)
I've used 9.2 client to connect to an 8.1 database, and an 8.1 client to connect to a 7.3.4? (was 7, definately... for some reason, 7.3.4 comes to mind), and I know there are settings in the server so that you can allow older versions of the client to connect, but I don't know how severe the penalty is for doing it in 9.2