File access problem with SMB and AFP on Mac OS X 10.4 SERVER Ok, I have about 10 macs, each with a different username/password that acces a mac os x server raid. File on the server, Photoshop, illustrator and indesign is used and open by anyone, anytime of the day !

now, on on station, the designer access BOTH the SMB and AFP share ate the same time... that case many file lock up and access. Even some corruption on some file when saving..

so here is the question, 


Can i block certain IP to log as SMB
Can i force the mac to access AFP only
and last question, do you suggest afp acces to server or smb, and why ?


*NOTE : Yes i know i can make shortcut on desktop, but they don't use it ! so now, i have to "force" them to work properly...
I have updated the server to 10.6 and mac to 10.6, the problem never came back !