Server side includes and navigation problems

[dsockrider]

I'm having a navigation problem with unique URLs that direct to a page that is below the organization structure of the navigation directory.

Example:
On the Chemical & Biomolecular Engineering website, I have the department navigation located at:
http://che.unl.edu/index-navigation.html

The navigation works fine while in a subdirectory, if the address is:
http://che.unl.edu/BioseparationsBiomaterialsGroup/

but...the lab has their own unique URL:
http://biomaterials.unl.edu/
using this URL, all of the navigation is broken because, the server side include doesn't find the nav file located in the directory above it.

Is is possible to use a server side include that uses an absolute URL? The current include doesn't allow absolute URLs.
so instead of using:
<!--#include virtual="/index-navigation.html" -->
is there an include or change that can be made so I could use an include that would be like:
<!--#include virtual="http://che.unl.edu/index-navigation.html" -->

[dsockrider]

Last website there weren't any problems because I kept all the navigation in the 'sharedcode' file. The problem with that was, people who have access to their own sites to update, didn't have access to their own navigation file. So this version, I've included the navigation and other files concerning a subsite within the same directory.

I don't want multiple versions of the same navigation because inevitably one nav set will get updated, while another doesn't. ...and sitewide updates don't work very well because it takes significant time to scan the thousands of pages in the engineering site to find a couple links that are updated. Having a Chem nav within a lab directory also opens up the possibility that someone maintaining a lab, student organization, event, etc. would update the department nav, making it inconsistent with the top level directory.