I cannot configure the new installed OpenProject 8.2.0 on CentOS 7 correctly. Application seems to work, but when I try to create a new account, fill in the form and click the button (Create), I get the Internal error. I checked the production.log, there is:

I, [2019-01-31T19:58:30.160246 #7568]  INFO -- :   Rendering user_mailer/account_activation_requested.html.erb within layouts/user_mailer
I, [2019-01-31T19:58:30.162607 #7568]  INFO -- :   Rendered user_mailer/account_activation_requested.html.erb within layouts/user_mailer (2.2ms)
I, [2019-01-31T19:58:30.229231 #7568]  INFO -- :   Rendering user_mailer/account_activation_requested.text.erb within layouts/user_mailer
I, [2019-01-31T19:58:30.231280 #7568]  INFO -- :   Rendered user_mailer/account_activation_requested.text.erb within layouts/user_mailer (1.9ms)
I, [2019-01-31T19:58:35.623069 #7568]  INFO -- : Sent mail to tomas.dvorak@praha.eu (5096.8ms)
I, [2019-01-31T19:58:35.623537 #7568]  INFO -- : Completed 500 Internal Server Error in 5792ms (ActiveRecord: 99.0ms)
F, [2019-01-31T19:58:35.624414 #7568] FATAL -- :   
F, [2019-01-31T19:58:35.624532 #7568] FATAL -- : Net::SMTPSyntaxError (500 5.5.1 Command unrecognized: "AUTH LOGIN"
):
F, [2019-01-31T19:58:35.624604 #7568] FATAL -- :   
F, [2019-01-31T19:58:35.624661 #7568] FATAL -- : app/controllers/account_controller.rb:635:in `block in register_manually_by_administrator'
app/controllers/account_controller.rb:634:in `register_manually_by_administrator'
app/controllers/account_controller.rb:558:in `register_user_according_to_setting'
app/controllers/account_controller.rb:366:in `self_registration!'
app/controllers/account_controller.rb:138:in `register'
app/middleware/reset_current_user.rb:47:in `call'

I guess, the problem is in SMTP settings. During the dialogs in "openproject configure" I set:

method: smtp
SMTP authentication: none
SMTP host: my.server.com
SMTP port: 25
SMTP domain: my.server.com

I verify the communication of SMTP server via telnet and server responded (telnet my.server.com 25).
Please, what is wrong?