[VM] How to configure for smtps protocol

[Rene]

My company is migrating to a secured smtp server.  It now uses the smtps
protocol on port 465 (instead of the regular smtp protocol on port 25)

Although I reconfigured the vm variables accordingly I can't manage to make use
of this new smtps server.

Here is my configuration file :

(setq smtpmail-smtp-server "smtps.company.domain.name")
(setq smtpmail-local-domain "company.domain.name")
(setq smtpmail-smtp-service 465)
(setq smtpmail-auth-credentials (("smtps.company.domain.name" 465 "login" "")))
(setq smtpmail-starttls-credentials nil)

(setq smtpmail-debug-verb t)
(setq smtpmail-debug-info t)

Besides I don't get any error message which leaves me with no clue on how to
debug  this problem.

Any help would be much welcome.

--
Rene