SMTP issues in 5.6a

[oliverr]

I have upgraded my build machine to 5.6a and am still having problems sending a very simple SMTP message. I have set up an SMTP server locally on the build machine and configured the smart host. All I need it to do is send the message locally, not authentication is required and I am using default ports. I continually get "Unspecified Error".

Regards,

Oliver.