Hi,
Thanks for your answer! I actually did do everything right, except for this weird phenomenon:
The SSL certificate actually supports 3 dns's: hrms.me; www.hrms.me; app.hunterhrms.com (you can view this certificate in your browser via any of these domains). However, the WCF service could only work with app.hunterhrms.com.
For some reason, the service's "DNS claim" was always app.hunterhrms.com, regardless of which "Host Name" I gave it in the site's "Edit Binding". In other words, even though the service's address included www.hrms.me (which is actually the name of the certificate),
its "DNS claim" was still app.hunterhrms.com.
Seems like a bug (or feature...) in the SSL certifcate, doesn't it?