Go | Connect to Server
smb://servername/sharename (in this case, acfiles is 10.1.16.112 currently)
username password
viola
Note:
for some servers
In 10.4, you may have to change your /etc/nsmb.conf
see http://support.apple.com/kb/TS1564 for details
In 10.5, see http://www.it.usyd.edu.au/~support/w/moin.cgi/OsxMountNetworkDirectory (among others)