Default Block Microsoft Windows 2000 SMB"" stealthed

Can anyone give me some detailed info on this ?
This is from my Firewall Log file

9/18/2004 12:00:53 AM,"Rule ""Default Block Microsoft Windows 2000 SMB"" stealthed (63.191.129.105,microsoft-ds(445)).","Rule ""Default Block Microsoft Windows 2000 SMB"" stealthed (63.191.129.105,microsoft-ds(445)). Inbound TCP connection Local address,service is (207.177.82.76,microsoft-ds(445)) Remote address,service is (63.191.129.105,1313) Process name is ""System"""

Thanks Bob