[Koha] Inventory with incorrect sorting

Hi all I upgraded Koha from 3.01 to 3.02.03.000 yesterday. Tools->Inventory doesn't sort the results the same way it used before. In the column "title" there is first the call number and then the title. I have a three part system for my call numbers. [Number]/[Number],[Number] Till 3.01 Koha gave: 1/ 1, 1 1/ 1, 2 1/ 1, 3 and so on. Now its like this: 10/10,10 10/10,11 till 10/10,43 (the last one in this shelf) 10/10, 1 till 10/10, 9 I liked the first sorting better :-( Is there a way to tell Koha how to sort the results of the inventory? Cheers Beda