Found info here: http://settings.email/sina.com-email-settings.html

In Thunderbird 'Menu icon' > 'New Message' > select 'Existing Mail Account'

Enter your name, email address and password. password is the same one you would use to access the webmail account.

click on 'Continue' Thunderbird may try to look up settings automatically.

Make sure you have 'POP' selected. If you need to modify settings then click on 'Manual Config' button

Incoming Server Settings

• Account Type: POP
• Username: Your email address is your username
• Server hostname: pop.sina.com
• Server port: 110
• Authentication: Password
• SSL/TLS: No

Outgoing Server (SMTP)

• Username: Your email address is your username
• Server hostname: smtp.sina.com
• Server port: 25
• Authentication: Password
• SSL/TLS: No

Thanks Toad-Hall. I did all the below, but Thunderbird only offers POP3 in the drop down, and when I test I get a message that sina does not support POP3

Any idea how to just use POP?

POP and POP3 are the same thing.