I'm having various problems accessing shares with dollar signs in their names (e.g., \\server\c$); however, there doesn't seem to be much consistency to the types of problems.

From my CentOS 4.3 box running Samba 3.0.21b or Samba 3.0.23a, mounting  \\server\data$ (a Windows Server 2003 DC) or \\domain\data$ (the same share, shared over DFS) using mount.cifs doesn't give any errors, and I can do an ls of the top-level directory, but when I try to do an ls of a subdirectory, I get the top-level directory listing again.

Using smbclient's tar command fails; it gets a directory listing of the subdirectory, but it tries to open each file in that subdirectory as if it were a directory, and so it gives the following error, repeated for each file:
NT_STATUS_FILE_IS_A_DIRECTORY opening remote file \WinAudit\wa_xml2html.xsl (\WinAudit\)
On other directory trees, it gives errors similar to the following:
NT_STATUS_OBJECT_PATH_NOT_FOUND opening remote file \Adobe\Adobe Acrobat 7.0 Pro
fessional\Common\Adobe\Acrobat 7.0\Uninstall\UninstManager.dll (\Adobe\Adobe Acr
obat 7.0 Professional\Common\Adobe\Acrobat 7.0\Uninstall\)
(It looks like the first error message is for files in top-level subdirectories and the second error is for files nested more deeply in subdirectories.)  It also gives errors similar to the following:
Server packet had invalid SMB signature! opening remote file \Adobe\Adobe Acrobat 7.0 Professional\program files\Adobe\Acrobat 7.0\R (\Adobe\Adobe Acrobat 7.0 Professional\program files\Adobe\Acrobat 7.0\)

I've also seen errors cd'ing into subdirectories from Samba 3.0.23, but I've been unable to replicate those; not sure if that's related or not:
client_check_incoming_message: received message with mid 11 with no
matching send record.
SMB Signature verification failed on incoming packet!