We have 2 WebApp in Sharepoint, one for the intranet and one for the
document center. There is some pages in the intranet that contains
link to some pages/documents in the second webapp.

Environnement First WebApp Second WebApp
Production http://intranet/ http://doccenter/
QA http://intranetqa/ http://doccenterqa/
Dev http://intranetdev/ http://doccenterdev/

To have a QA environnement that represents almost exactly the
production environnement, we are planning to restore the backup of the
site from the production to the QA environnement. The problem is that
the page in intranetQA will still contains link to http://doccenter/
and not http://doccenterqa/.

We don't want to put the 2 collection in the same WebApp for
performance and security reasons.

What's the best way to solve this ? Is there someting in Sharepoint to
help me with this situation ?