Authentication Required Error

Hi Manuel,
The class is great, thanks for share it!
I can't figure how to make it works with a gmail account.
In gmail says that you need to configure your SMTP client with "My server requires authentication".
I leaved empty authentication_mechanism and I get this:

Resolving SMTP server domain "smtp.gmail.com"...
Connecting to host address "209.85.163.109" port 465...
Connected to SMTP server "smtp.gmail.com".
S 220 mx.google.com ESMTP u25sm3607325ele
C EHLO localhost
S 250-mx.google.com at your service, [XXX.XXX.XXX.XXX]
S 250-SIZE 28311552
S 250-8BITMIME
S 250-AUTH LOGIN PLAIN
S 250 ENHANCEDSTATUSCODES
C MAIL FROM:<XXX@gmail.com>
S 530 5.5.1 Authentication Required u25sm3607325ele
Disconnected.
Cound not send the message to YYY@gmail.com. Error: 530 5.5.1 Authentication Required u25sm3607325ele

Thanks in advance.
Leo.-

Sorry, I've fixed my application, I've filled the pop3_auth_host.
Now I've set it as empty and it works great.
Thanks Manuel, your work is excellent!
Leo.-

Same problem
Thanks for the suggestion
now it works fine with pop3_auth_host=""
is it my mistake or a bug?
bye
Angelo