Cyrus saslauthd PAM authentication Issue

[Xue, Jack C]

I am experiencing a Cyrus-SASL and PAM authentication issue here: 

I have configured a Cyrus-IMAP Server to use saslauthd for authentication.
The system is a RHEL4 Update 3 64bit and runs the RPM package comes with Redhat. The Cyrus-SASL version is 2.1.19, Cyrus-IMAP version is 2.2.12-3.  

Here is my /etc/imapd.conf:

configdirectory: /imapconfig
partition-default: /imapstore/imap01
partition-1: /imapstore/imap01
partition-2: /imapstore/imap02
defaultpartition: default

admins: cyrus_admin cyrus_murder
sievedir: /imapconfig/sieve
sendmail: /usr/sbin/sendmail

hashimapspool: true
sasl_pwcheck_method: saslauthd
sasl_mech_list: plain

When I do a:
$ imtest -u username -a username localhost 

This is what I see in the /var/log/messages Log:

saslauthd[6586]: PAM unable to dlopen(/lib/security/pam_stack.so)
saslauthd[6586]: PAM [dlerror: /lib/security/pam_stack.so: cannot open shared object file: No such file or directory]
saslauthd[6586]: PAM adding faulty module: /lib/security/pam_stack.so
saslauthd[6586]: do_auth: auth failure: [user=username] [service=imap] [realm=] [mech=pam] [reason=PAM auth error]

I checked and there is a /lib/security/pam_stack.so on the server. The rest of PAM authentication process is working correctly as it should be. 

Also the server has both /lib/security/pam_stack.so and /lib64/security/pam_stack.so. Will that be problem when the 64bit sasl library tries to use 32bit pam library?

I am confused. I am hoping someone can give me some advice. 

Thanks. 

--------------------------------
Jack C. Xue         RHCT
Computing Services Systems Group
Marshall University
Drinko Library 423C
1 John Marshall Drive
Huntington, WV 25755-5320
E-mail: xue at marshall.edu
Phone: (304)696-6396
http://JackXue.GooglePages.com