Open Opera Mini on your mobile phone.
Scroll to the Speed Dial entry you wish to update or edit.
Perform a "long hold" on the Speed Dial entry. This can be done by holding the " Center" key if you're using a trackball or directional key or by pressing and holding the number that corresponds with the Speed Dial entry. If you're using a touch screen phone, you can touch and hold the entry you want to change.
Select "Edit" from the context menu that appears and either type in the new address you wish to use for the Speed Dial or select one from your browsing history.