I find that I like to obtain AFS tokens on login but I have also found 
that once in a while our network is down and this can make getting into 
a machine problematic. What I have done is modify the afs script in 
/etc/init.d to check if the servers are available and if so modify the 
/etc/pam.d files appropriately to enable tokens granting on login 
otherwise go back to the default setup without the AFS authentication.
I have put a set of files and a script to set this up customized for our 
AFS cell here at the University ofd Alberta in a tar file on my website 
if anyone is interested. This should be regaurded as very preliminary 
since I have not done extensive testing but others may find it useful. 
The location of this  file is 
http://www.ualberta.ca/~barton/AFS/SL/SL40Openafs.tar

-- 
Bob Barton <[log in to unmask]> 
Local Area Administrator (780) 492-5160
564B Chemical & Materials Engineering 
University of Alberta,
Edmonton Alberta, T6G 2G6