First! You must to download Opera Mini 4.2 or Opera Mini 5beta2 and follow the proxy settings below.

=> Menu > Settings > Connection > Access Point

Access Point Settings

=> Press options > new access point > use default settings
¤ connection name
any name
¤ data bearer
packet data
¤ access point name
internet
¤ user name
none
¤ password
no
¤authentication
normal
¤ homepage
none
=> Press options > advanced settings
¤ networt type
IPv4
¤ phone IP address
automatic
¤ name servers
automatic
¤ proxy server address
80.239.242.19
¤ proxy port number
80
=> Press back 3x and exit. Then open your Opera Mini.