TreeCache with concurrent puts becomes inconsistent

Concurrent puts using tree cache api store data values in the tree but the structure of tree can become corrupted. Namely: node.getChildren() for a parent node might not include the child node even though the child node exists and has some data.

This makes it difficult to reliably use the tree cache structure to mirror a corresponding tree-like business data structure (e.g. materialized from a database).

This can be readily reproduced with a local cache. A unit test is attached to the referenced forum topic.