2011-05-21 09:23 AEST by Arthur Barrett - If you checkout a module, any 'empty' directories are automatically pruned.

If you update a module (-d 'build directories like checkout') then they are added/not pruned.

This is clearly inconsistent.  I suspect it's not new in CVSNT, and is some 'old' behavior we need to continue 
to support for 'compatibility'.  But we could 'fix' it but have a 'compatibility' option (enabled by default) to 
do it wrong.