search\BooleanClause.java - Text files are different - Java Enum overrides ToString() -> 
                                                       can't do that in .NET, it will always choose the 
                                                       base class instead of the extension method, if that's how
                                                       we choose to implement.
store\LockStressTest.java - Text files are different
store\MMapDirectory.java - Text files are different - PORT ISSUES
store\NIOFSDirectory.java - Text files are different - PORT ISSUES


util\DummyConcurrentLock.java - New in 3.x (NOT NEEDED IN .NET?  Can just use new Object() for a dummy lock) (used in MultiSearcher)
util\NamedThreadFactory.java - New in 3.x
util\ThreadInterruptedException.java - new in 3.x (NOT NEEDED IN .NET?)