WL#4368: Fix NDB/J Unit Tests

Affects: Connector/NDB-0.7   —   Status: Complete   —   Priority: Medium

There are currently outstanding test failures in the junit test suite. Most
tests pass, but some fail and some actually segfault. All of the tests should
pass (of course) but this may mean fixing bugs in (a) the tests (b) the code (c)
NDB API itself.