On SP2 I had CIFS stop responding / crashing every 1 to 48 hours, afp would stop working every 1 to 7 days. I worked with Novell and disabled "snapshot - file level" on all of my volumes and the problem went away.

On a side note (This is unofficial). I got a call from a NSS team member about the problem and another issue. He said that NSS has hit maturity and will no longer be developed. They are working on btrfs as a possible replacement.

Joel