I have a requirement for special access acl's from cifs clients. In particular for directories to which users can add files but can not then remove them.
Fair enough. What you need is either the "special" Windows NT directory permission set called "Add" (actually Write and Execute) or perhaps "Add & Read" (actually Read, Write and Execute). Not a problem.
I understand this to be a function of NT permissions, the options all seem to be there for the filer but don't seen to have the desired effect.
What effect are you seeing?
Can anyone tell me if this is supported functionality.
Absolutely. Assuming you have configured the filer to support NTFS semantics in the portion of the file system being accessed by your Windows clients, you should find that these directory permission sets will restrict and allow various client operations exactly as they would on a bona fide NTFS file system partitions of a Windows NT server.
Keith