I managed to get Gmail‘s POP3 and SMTP support (via SSL/TLS, which they require) working on my spiffy new Sony Ericsson W600i, but not without a bit of headache.

After setting everything up, using their provided information, the W600i was complaining about not trusting the SSL certificates that Gmail uses, and would refuse to send mail because of it (although it would still receive mail, after asking you to acknowledge a stern warning). In order to get it working I needed to install two certificates on my phone:

• “Equifax Secure Certificate Authority” (direct link)
• “Thawte Premium Server CA” (ThawtePremiumServerCA.cer inside the zip file)

In order to get the phone to accept and install them, you have to use OBEX Object Push (aka “Send File…” under the Bluetooth menu in Mac OS X) to send the .cer files to the phone. The “Send File…” client will complain that your the device doesn’t accept the file type you are sending it; choose the “Send Anyway” option, it works fine. If you just transfer the files as regular files, you will see them on the phone, but will have no option (that I could find) to install them.

The phone is rockin’ now!

I’ve provided the above information here, because figuring out which certificates I needed, where to get them, and how to install them is like pulling teeth. I got each tiny bit of information from various different places. Hopefully this page will index well and help others. :)