Yes, there is an issue with the DNS-323 with Snow Leopard. D-Link fixed their problem with the beta FW version 1.08b5 (which I upgraded to just before upgrading our home machines to Snow Leopard and have been running without issue for a couple months now; I even risked it and didn't back up my data).
Or, I believe a temporary fix is to change the password on that share to something that's all-numeric.