But an email address is not a full name either, so don't put it there, 
or live with the fact that it's considered a name, if you tell Turba 
that it is a name. What if you are using the name field for a company 
name and this name happens to contain a "@" character?

Because an email address clearly isn't a lastname. Perhaps if it were 
to strip the username from the email address and use that it'd be a 
reasonable (though unlikely) guess as to the last name.

Yes, and why is this broken behaviour?

With the current code if the Name value is set to an email address, 
then that function causes that email address to also be displayed as 
the last name.



e.g. in the list of users you'd get something like

Name                          First Name    Last Name                  E-mail

eg@example.com                            eg@example.com     eg@example.com

Why is this necessary, the email address should be considered as a 
single name part?

Prevent Turba from attempting to automatically guess the lastname if 
name is set to an email address.