immutable bits

[Greg Whynott <greg@xxxxxxxxxxxxxxxxxx>]

We converted all our file systems to XFS.  On the ext3 file systems we
would set the immutable bit on some dirs.  Is there something  similar I
can set on a directory within an XFS filesystem?  

We don't want folks with root to be able to delete dirs and files
without a few extra steps taken.

thanks folks,

greg