1) set profile as "Project Leader" to both managers
2) Affect both managers to project
3) Configure mail sending (for instance on any change) to send emails to project leader

That's all B)

Thanks,

And for only one ticket, can I have this behaviour (set multiple users to be notified about progress of Ticket #XXXX) ?

No,
You can configure this behavior for a given ticket type, but not for one ticket only.

Or you should use "send mail" button on the ticket....

Ok Thanks for reply

What do I have to do if I would like it to be on future versions ?

A simple comment here would suffice ? or rather it has to be voted by a number of users ?

Hi,

This request is very specific and should not be included in community version.
(personnaly, I don't really understand the need).

If you wish to have it implemented, it could be done through specific evolution.
Have a look at Evolution service on the site. If you agree, you can send exact requirement at support@projeqtor.org.
I'll send you a quote.

Ok will do so

Just for Information : this Functionality is the same as offered by Basecamp, Bitrix24 or Redmine, that is "Watch for a ticket" that make sens if you have a special request, on which other tickets are strongly related, and you want to be informed by email when it is finished ...

best regards

OK, I understand better the need, to have "Watch this item" function.