[Djigzo users] Another question about domain certificates

Good evening after my last posting about domain certificates, I decided to test this feature. Djigzo accepted the email address *(a)abc.com and I was able to configure this "user". When I now download the certificate for *(a)abc.com and import it on another Djigzo system, will this system really use this certificate for every email to addresses that end on abc.com?? And if it does, where do I get an official wildcard certificate? I have checked the website of Verisign and Thawte, but couldn't find an offer for wildcard email certificates, only for single email addresses. Best regards, Stefan