Domain forwarding question
 

A question for you server gurus out there. I have a domain that is being forwarded to different address. How do I set it up so that when somebody types in domain.com/whatever.html it will go there instead of going to not found page on the server where the domain is hosted at? Right now I can only get it to forward to one page on the different address. I want it to go to whatever page or directory while still masking the original address. (Use frame source). I know its possible as Ive seen it done but I can't seem to figure it out.

Thanks