what are these error messages?

[Paula J. Lindsay]

Hi everyone,
I installed this system and put it on the network early last week.
Everything worked fine until yesterday. When a user now logs on, he gets
the error message "can't find home" and the machine just logs them out.
Here is what is in the /var/log/messages:

Nov 7 12:46:09 chemino4 automount[15697]: expired /home/lpastern
Nov 7 12:46:20 chemino4 rpc.statd[4695]: recv_rply: can't decode RPC
message!
Nov 7 12:46:51 chemino4 last message repeated 2 times
Nov 7 12:47:24 chemino4 last message repeated 3 times
Nov 7 12:47:38 chemino4 sshd(pam_unix)[15701]: session opened for user
paula by (uid=30301)
Nov 7 12:47:38 chemino4 automount[4895]: attempting to mount entry
/home/paula
Nov 7 12:47:45 chemino4 RISC: SU: (OK) paula on /dev/pts/0
Nov 7 12:47:51 chemino4 gdm(pam_unix)[5691]: session closed for user
kuniyuki
Nov 7 12:47:51 chemino4 modprobe: modprobe: Can't locate module
char-major-10-134
Nov 7 12:47:53 chemino4 rpc.statd[4695]: recv_rply: can't decode RPC
message!
Nov 7 12:47:55 chemino4 rpc.statd[4695]: recv_rply: can't decode RPC
message!
Nov 7 12:48:01 chemino4 gdm(pam_unix)[5691]: session opened for user
vnmr1 by (uid=0)
Nov 7 12:48:01 chemino4 automount[4895]: attempting to mount entry
/home/vnmr1
Nov 7 12:48:01 chemino4 automount[15774]: lookup(yp): lookup for vnmr1
failed: No such key in map
Nov 7 12:48:01 chemino4 gdm[5691]: gdm_slave_session_start: Home
directory for vnmr1: '/home/vnmr1' does not exist!
Nov 7 12:48:24 chemino4 rpc.statd[4695]: recv_rply: can't decode RPC
message!

Does anyone know why the users lpastern and vnmr1 and kuniyuki aren't
able to locate their home? I do not know what "recv_rply: can't decode
RPC message" means, could this be causing the problems? I'm going to try
to google this error message but thought I would ask the group first.
This machine is running Red Hat Enterprise Linux WS release 3 (Taroon
Update 2). Any help would be very much appreciated.
Thank you,
Paula

-- 
--*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*
  o The			Paula J. Lindsay, IT Analyst III
 /        	 	Research Computing, TPC21
o   Scripps		phone:  858.784.9378
 \			fax:    858.784.9301
  o Research 		email: paula at scripps.edu
 /                    
o   Institute						
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