The three overloaded functions for itemCharPrice do not work - they try and call itemPrice() rather than itemCharPrice() but there is no overload with the appropriate signature (fortunately!).
It has been like this at least as long as the file has been in SVN, and it's fairly low impact, as the salesOrderItem and itemCharacteristicDelegate classes both call the actual implementation, not one of the broken overloads.
Steps to reproduce:
Read more at http://www.xtuple.org/mantis/view.php?id=8146