what i do is after the project is complete, run a 
perlscript over the archive which does some inline 
regexp pattern matching / replacing. Something like 
this:

s/(\.\.\/)
*external\.html/http://mysite.com/external.html/g;

My external page is essentially the same as the 
supplied one (ie: I make use of the 'link' parameter), 
but if I didn't want that, then something like this 
would do:

s/(\.\.\/)*external\.html\?link=/http://mysite.com/external.html/g;