Here's the settings GMail requires, just thought I'd post them here in case you hadn't seen them. I can't check with YAM or simplemail for you, but hopefully this helps. :-)
Incoming Mail (POP3) Server - requires SSL: pop.gmail.com
Use SSL: Yes
Port: 995
Outgoing Mail (SMTP) Server - requires TLS: smtp.gmail.com (use authentication)
Use Authentication: Yes
Use STARTTLS: Yes (some clients call this SSL)
Port: 465 or 587
Account Name: your Gmail username (including '@gmail.com')
Email Address: your full Gmail email address (username@gmail.com)
Password: your Gmail password
