Checked with my server and 25 is not blocked. Still can't verify. Here is error text from an attempt
[01] 12/18 21:16:13 MX <[email protected]> -> [mail.melomec.com]
[01] 12/18 21:16:13 > CONNECT TO: [mail.melomec.com]
[01] 12/18 21:16:28 > CONNECT TO: [mail.melomec.com] (Retry #2)
[01] 12/18 21:16:43 > CONNECT TO: [mail.melomec.com] (Retry #3)
[01] 12/18 21:16:13 MX <[email protected]> -> [mail.melomec.com]
[01] 12/18 21:16:13 > CONNECT TO: [mail.melomec.com]
[01] 12/18 21:16:28 > CONNECT TO: [mail.melomec.com] (Retry #2)
[01] 12/18 21:16:43 > CONNECT TO: [mail.melomec.com] (Retry #3)