You can setup a wildcard subdomain in plesk using a /conf/vhost.conf file on the virtual host ( eg: ServerAlias *.dtbaker.net )
If you then go and create a static subdomain ( eg: foo.dtbaker.net ) using the plesk interface there is a good chance that the previous wildcard subdomain will take precedence ( because it was setup first in plesk ).
We have to make the subdomain apache configuration ( foo.dtbaker.net ) load before the wildcard configuration on the main site ( dtbaker.net )
On Centos I created this file: /etc/httpd/conf.d/yyy.foo.dtbaker.net.conf containing:
This way apache/httpd will load the yyy.foo.dtbaker.net.conf file before the plesk zz010_psa_httpd.conf file in conf.d directory.
(name it starting with “y” so that the other configs (eg: php) load first)