In the items bag, the first 77 items can be modified, but others can not.
In the medicine bag, the first 12 items can be modified, but others can not.
In the TM/HM bag, the first 27 items can be modified, but others can not.
There are not so many items in the berries bag and the key items bag, so I don't know whether these two bags get the same bug.
Both B/W and B2/W2 saveifle is affected.