Do not want the default browser to be prompted

Hi
I purchased my BB from UK, here in Bangladesh, no carrier provider is giving me their internet access on that. I did it manually from APN settings. Then I installed Opera Mini 3. Opera works fine, but once I want to download anything by Opera, it prompts the default browser, which always asks me to ensure the WiFi connection. I dont have any WiFi connection around. Then finally, it does not allow me to download at all! So embarrassing. How can I fix this problem. please help.

regards