[i18n] The freebusy information not showing if chose other lang than english

[Zmylna]

Hi.
Some time ago I finished the fight with inoperative Polish language. In  
the end it worked by removing the line putenv('LANGUAGE=' .  
$lang_charset); from the file registry.php
Now i can log in to horde with polish language but the freebusy legend  
stops working :(

If i log on to horde with the chosen language English the freebusy legend  
shows up. If i log on with selected language Polish freebusy legend no  
longer shows. Only empty blocks.

Please help.