Hi
I believe this is an old bug, but I noticed it in 9.3.0. Steps to reproduce:
1) Open connection. Create an SMTP connection. Add some random address, port 25, and click ok
2) In manage connections it says port 25. All good.
3) Open connection again. It says 21. If you send an email using the connection, it works because port 25 seems to be hardcoded in the code. However if you click on the Test button, it uses the port in the image, and therefore fails (21 is not an smtp port).
I believe you find the same bug in Ftp connections as well.
Thomas