By default, detailed logging in smartermail is not enabled. You need to enable it manually by following below steps:

1. Login to SmarterMail as an Admin.
2. Click on Settings.
3. Click on Log Settings.
4. Select tab Log Detail Level
5. Change the SMTP Log Level and Detailed Log Level to Detailed.
6. Click Save.

You will be able to see delivery logs, SMTP logs in detail once you enable this option.