Hi,

In Oracle, plain_site, when i finish the signup of a new user with a non existente email address, i get the following error message in debug:

An error occured while sending or receiving mail. RCPT TO failed with error: 550 5.1.1 <cleverti@mail.ez.no>: Recipient address rejected: User unknown

Steps to reproduce

Enter ezpublish in plain_site
click the "login" button
Click the "Sign up" button
fill in the user fields, using an *NON-existent* mail
click on "register" button

After the last step, the error appears