in reply to Running a single instance of a Catalyst app across multiple subdomains with single sign-on
I should think that you should be able to point each virtual host to the same instance and have it Just Work. An external FastCGI process would handle this nicely, or a standalone HTTP::Prefork process.
As far as the SSO stuff, you should be able to do something like a wildcard as you suggested so that the base domain has access to all the subdomain cookies.
mtfnpy
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