Similar to the other fairly recent changes where you can pass in a different template name for login, logout, password_change[_done], password_reset[_done] in urls.py, the email template should also have the ability to be overridden. For example, in my case, I'm putting all login related stuff in the accounts template directory. Without this functionality you always need a registration template directory.
I've got a proposed diff that is tested and is working on a site I'm developing. I'll submit it after posting this. I'm not sure of the correct way to submit a patch so I'm using "svn diff > email_template.patch".
What this will do is allow one to override the email template you set it in your urls.py like so:
(r'accounts/password_reset/$', 'django.contrib.auth.views.password_reset', {'template_name': 'accounts/pwreset.html', 'email_template_name': 'accounts/pwreset_email.txt'}),
Note the new key "email_template_name" is new.
