As Nischay pointed out, that's not an issue with your setup. Reverting the mentioned change will not get rid of the bug (in fact you'll have a few more then), though it will make them all fail more silently. The issue here is that an empty string is passed as property id toaddToUsageCount. If you could pinpoint where this empty string is coming from, that'd be great.
Jeroen De Dauwhttp://www.bn2vs.com
Don't panic. Don't be evil.