[OpenAFS-port-darwin] OS X hangs when accessing files

[Systems Administration]

Server:  Linux (Gentoo) 2.4.26 - OpenAFS 1.2.11
	MIT-Kerberos5 KDC

Client: Mac OS X 10.3 - OpenAFS 1.2.11
	Kerberos-Extras
	aklog


Problem:
When I attempt to access any file on a mounted volume the Mac OS client 
hangs.  This is the same in Finder or as a shell access.  I have 
checked the filespace on Linux clients - no hang at all.  The only way 
to get the OS X client to cleanly un-hang is to force stop the 
bosserver on the Linux server and restart.  Then the client does 
timeout and OS X becomes responsive again.

TCP dump shows traffic between the OS X client and the AFS server when 
accessing directories leading up to the file access - and rarely I can 
get the very first file access, read/write or delete, to complete 
sucessfully - however its an illusion to the user as the absolute next 
access ALWAYS locks up, directory or file access.

I get no logs, no kernel panics, nothing on the Console, nothing in 
/var/db/openafs/etc/AFSLog.

No errors on the AFS server, an no problems on the network for these 
clients to access other resources on the same machine.  A ping flood 
shows about a 20% packet loss between the server and client machine, 
connection is by switched 100mb ethernet (from client to hub) and a 
1000M fiber switch (servers on Fiber switch) between the hub and 
server.  Ping flood has 0 packet loss on the return from the client and 
when doing a non flood ping from the server so this appears to be 
dropped packets from the fast Gigabit side to the slow 100Mb client.

Are there any other troubleshooting steps I can perform?

Ted