Troubles with OPERA

That depends how the operator is allowing http traffic. This is defined by the Access Point you have to set. Some operators use the same AP for all kind of traffic (WAP, MMS, internet, etc.), some choose to segregate the different protocols.

You could first try by defining an Access Point (in connection settings) using "internet" as the "Access point name", don't mind about the other settings like name or pwd. If that doesn't work, ask the operator. Some operator don't allow internet traffic at all...

you need to use an Internet access point not just a WAP one. the settings are network dependent. search the forums and you may find them. or check Opera's forums, they have some settings stored on there,
You may need to contact your operator to turn it on. and should be aware of the charges, as it is sometimes different from wap

thanks mig29 the thing with changing 'access point name' solved my problem. thx a lot.