The opera mini problem is not an easy one to solve. While we know that one problem is connected to clock and zone settings, but there is one other problem with local settings and characters which cannot be addressed without an input from the Opera Mini developing team. While we wait for their answer, this issue will remain unresolved, I'm afraid. There's only one workaround that seems to work, and that is to change the language to English (US) and then login on the default page.
I would like to ask all users for some patience.
Thank you all for your input!