EX2013 SSL Outlook Client Issues - Internal and External Names are Different

I have just migtated from exchange 2007 to exchange 2013 sp1. Internal Domain name abcd.local and External Domain name 1234.com. I have purchased a new SSL Cert from Go Daddy with mail.1234.com and autodiscover.1234.com. Everything is working fine except my internal Outlook clients. They receive an SSL error because the names don't match which i totally understand. I have tried adding an autodiscover SRV record to DNS that points to mail.1234.com and changed the internal and external virtual directories to the external url. Neither of these have helped.

So the question is how do i get the internal outlook clients to work without the SSL error?

Thanks.