Permalink behavior

I have a WP site with its WordPress Address set to http://www.ttpsoftware.com/eauvivreWP in the General Settings. The Site Address is set to http://www.eauvivrewinery.ca. In the Permalinks settings I have selected the Post Name option. However, this is not working. All page and post links in the front end return an Internal Server Error.

It appears that I can’t use any permalink option other than Default if the domain name in the Site Address is different from the the domain name in the WordPress Address. I would really like to see this addressed in a future release. I think anyone who hosts WP sites for clients but is not a domain name registrar would appreciate this functionality.