Hmmm, I've not noticed anything like this, and I've been using ubook for years (including 0.9f ang currently 0.9g). I just had a bit of a look through the options and can't find anywhere where you could turn that on or off.
Did you uninstall the older version before upgrading? I haven't done this, but it might be worth uninstalling then reinstalling to see if that fixes the problem. If it's still happening, I'd shoot the author an email. He's been very punctual and helpful for me in the past.