I've seen a few people with the same problem - this is my way of saying 'screw you' to Adaptec.
I have a snap 4100 that no longer works in my Server 2003 Active Directory - I contacted Adaptec support and was told they actually expect me to PAY for a maintenance contract I will never use to fix their OS problem. I refuse to pay for updates like this and if everyone refuses then we may see a change in attitude from vendors.
There is however a workaround for this problem if you have a Linux (or other UNIX) box running SAMBA3 with Winbind.
Join the *NIX machine to your Active Directory (see WinBind docs)
Turn on NFS sharing in the Snap Server.
Edit the root$ share and add an NFS entry for UID 0 from the IP of your *NIX machine.
Make a directory on the *NIX machine for a NFS mount -
e.g. mkdir /mnt/snap
As root, mount the root$ share of the snap using NFS from the *NIX machine
e.g. # mount -t nfs ip.of.snap.server:/root$ /mnt/snap
Edit your /etc/samba/smb.conf to share the mounted folder to Active Directory users.
This should get you up and running. Hope someone finds this useful.