Mapping context to root of website

[Ronnie Tartar]

Is there anyway to map a context to the root of a website.
 
For instance:  http://www.test.com/context/ to
 
http://www.test.com/
 
I know I can do this by creating mulitple Tomcat Instances but this is
not very efficient on resources.
 
I have done it with Mod_warp with success but need to do it on IIS and
Apache.
 
Is there a doc out there somewhere?
 
Thanks in advance.