Hit ENTER after each Tag to add it to your post; Numbers in parentheses represent the Tag's usage.
So the good news is that this version will indeed support negotiating TLS1.2 !!! That is awesome and thank you developers!
The bad news is that when you install a Cert with a SHA 256 Hash and it negotiates with a SMTP server that utilizes a newer TLS 1.2 cipher suite such as TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA256_P256 will cause the following error:
[2015.08.18] 03:19:55 [x.x.x.x][X] Exception negotiating TLS session: System.NullReferenceException: Object reference not set to an instance of an object.
[2015.08.18] at MailService.TcpServerLib.Common.PooledTcpItem.ConvertToSSL(IPBindingPort setting, Log log, String sessionId)
[2015.08.18] at MailService.TcpServerLib.Common.PooledTcpItem.ConvertToSSL(IPBindingPort setting)
[2015.08.18] at MailService.TcpServerLib.SMTP.SMTPSession.#W8()
Basically it will negotiate TLS 1.2 just fine but if it is asked to use a cipher suite introduced with TLS 1.2 it breaks down and cries uncle...