how to configure IIS6 and up to use .net 3.5 with a VDir of .net 1.1?

I have a site built on .net 3.5 I need to have a virtual directory in it for another site built on .net 1.1. I have created to application pools in IIS开发者_C百科 and each are set to the right version number but it still doesn't work.

Thanks

Remark: just a remark that iis has the no .net 3.5 among its options. In fact .net 3.5 runtime is the same as .net 2.0 runtime, its just the Base class library which is different but the runtime versions are the same