I use the plugin for copying artifacts to a Windows-based file-server. If the job runs on the Linux-based master, all is ok (but a little bit slowly).
If the same job runs on a Windows2008-64bit-based slave, the job fails on copy after a very long time with an exception. See the fragment of the console-output (I have removed all specific strings from our company):

CIFS: Connecting from host [******]
CIFS: Connecting with configuration [******] ...
CIFS: Removing WINS from name resolution
CIFS: Setting response timeout [30.000]
CIFS: Setting socket timeout [35.000]
CIFS: mkdir [smb://******@****/war/]
CIFS: cleaning [smb://******@****/war/]
CIFS: copy [smb://******@****/war/****.war]
CIFS: Disconnecting configuration [******] ...
ERROR: Exception when publishing, exception message [Plain text passwords are disabled]
Build step 'Send build artifacts to a windows share' changed build result to UNSTABLE
Finished: UNSTABLE

The access to the file-server over the windows-fileexplorer on the same slave works without any problems.