If you configure the portal to use ldap for login, it is possible to use the user's email address for login, provided, of course, that the ldap information includes the user's email address (I know that MS Active Directory stores the email address).
and when using a DB implementation?
is there any way?
the simpliest way i can think now is using your own registration portlet where you ask for an email and put it in the userName property of the Identity API, as well as creating your own login.jsp page, where you replace the login label with the word email. (report to the portal reference guide, where youn can find the modules used for account creation in the identity API chapter (HibernateUserModule.createUser or something like that...)
hope this help,
As long as the email address is in the database, then yes you can create a login module that uses the email address as the user's name. (Actually, you can use any information available in either ldap or a database as the login information, such as phone number, date of birth, even street address, though it prevents confusion if the information is unique.)