When I submitted bug #3562 for Redhat Linux I entered
the address firstname.lastname@example.org in the Cc: field.
After hitting 'Commit' I got a login screen where I
entered my e-mail and password and hit 'Login'.
I got a report "The name 'email@example.com' is not a valid username. Please hit the Back button and try again"
I entered MY e-mail in login,
which is firstname.lastname@example.org , I also entered my password correctly.
I used the Lynx 2.8.1rel.2 browser on a Redhat Linux 6.0 / i386 system.
Bugzilla used to require that whatever email address that was entered in the Cc:
field had to be already a Bugzilla member for the address to be valid. Which is
still the case but now Bugzilla will create an account for the new user
autmatically and mail the password to the person's address entered in the Cc: