Hi Alan,
Yes, you could do that, run Gossamer Mail on a certain domain, say webmail.com, and then setup a sub-domain fr.webmail.com that would redirect to webmail.com calling up the French templates and also the French domain.
You could also setup en.domain.com which would also redirect to webmail.com passing in the domain name and requesting the English templates.
If you have all the domains on one dedicated Linux/Unix machine, you could even set it up so that Apache mod_rewrite preserves the sub-domain name instead of showing the webmail.com address.
Should you wish to host with
http://www.gossamerhost.com, we can setup the above for you at no charge, but if you are hosting elsewhere, you might want to check with that hosting company that they can set that up for you.
Only one installation of Gossamer Mail is required to do all of the above, which simplifies everything from template modifications to database management, and especially when it comes time to upgrade the program to the next version.
Jack.