No, a mailto link will pop up a new email window in Thunderbird or Outlook or something else, depending on what's configured as the default mail client. This is the recommended solution, as it depends on the unauthenticated user's email tools.
To enable a template-based mail window, you'll have to change a few things:
- templates/rt/rt.tpl: Disable the $isUserLoggedIn check around the link to emailColleague
- Disable the logged in check (whether the user object evaluates to true) in pages/rt/RTHandler.inc.php, in the emailColleague function
Be aware that this essentially leaves OJS open as a mail relay!
Open Journal Systems Team