I think you bought just the uk version but in Poland
The post of forest is clear the game has been translated into polish.
<copyright mark> CDV Software Entertainment AG. All rights reserved. CDV, CDV logo and Divine Divinity are registered trademarks or trademarks of CDV Software Entertainment AG or Larian Studios in the United States of America and/or in the United Kingdom and/or in other countries. USE AT HOME ONLY. Unlicensed copying, lending (...) is strictly forbidden. (this text is written on each CD-ROM container; I don't know where the box (in which the game was sold)is but I think nothing more is printed there)
My conclusions :
1- It's a pirat version but i don't really think it is because a pirat don't take the time to translate the texts.
2- CDV has made a polish version of the game without informing Larian.
Barta