We experience problems with performing any operation (deleteall, get etc.) on a znode that has too many child nodes. In our case, it's above 200k. At the same time jute.max.buffer is 4194304. Increasing it by a few factors doesn't help. This should be either solved by limiting the number of direct znodes allowed by a parameter or by adding a hard limit by default.
I am attaching some screenshots of the commands and their results. What's interesting the numbers from getAllChildrenNumber and stat (numChildren) commands don't match.