This week's book giveaway is in the OCMJEA forum. We're giving away four copies of OCM Java EE 6 Enterprise Architect Exam Guide and have Paul Allen & Joseph Bambara on-line! See this thread for details.
Offhand the most likely guess is that children() and breadthFirstEnumeration() return different enumerations. Maybe children() returns only immediate children, and breadthFirstEnumeration() returns grandchildren, etc. as well? Are these two methods supposed to return the same enumeration, or not?