Name: Your Name (What ever you want)
Email: Your email address is your username
Password: Your sina.com account password
Description:
Click Next Button
Hostname: pop.sina.com
Username: Your email address is your username
Password: Your sina.com account password
Hostname: smtp.sina.com
Username: Your email address is your username
Password: Your sina.com account password
Click Save Button
Use SSL: None
Authentication: Password
Server Port: 110
Use SSL: None
Authentication: Password
Server Port: 25
You can login sina.com and Signup for sina.com new account on your iPhone from here.