Can't delete an old OpenJDK directory because of NUL files

[Pete Brunet]

On WinXP I'm unable to delete an old OpenJDK directory because there are
a lot of files named NUL which Windows is not able to delete. 

I can delete them by renaming them one by one with 'ren
\\.\c:\full_path\nul xyz' but that would take a long time.  Is there a
command available in cygwin that will delete the directory?  Cygwin rm
also fails to delete files named NUL.

Pete