Using the Lucky four leaf clover for combat

[Bubbles]

The AI constantly uses the (i don't remember it's name exactly) the lucky 4 leaf clover (the one that changes your die roll to any number 1-6) to roll a six when doing combat with me. When they choose a 6, the game turns that number into a 15, making them win no matter what.

All expansions and characters are installed, using windows 7 64bit
This bug is repeatable, by different non-basic characters. (haven't tried on a basic char yet)