if (newItem == null) return false;
removeItem(-1, item.getItemId(), item.getCount());
// Add changes to inventory update packets
if (oldItem.getCount() > 0 && oldItem != newItem) playerIU.addModifiedItem(oldItem);
else playerIU.addRemovedItem(oldItem);
if (newItem.getCount() > item.getCount()) ownerIU.addModifiedItem(newItem);
else ownerIU.addNewItem(newItem);
// Send messages about the transaction to both players
if (newItem.isStackable())