I am running into a problem with using LDAP authentication on an SGI
ProPack 2.3 linux server. The configuration files are direct copies
from a RedHat linux server that works perfectly. I have been doing
most of my testing via the console login to make things a little more
cut and dry.

The message "User not known to the underlying authentication module"
appears when a correct LDAP username and password has been entered.
The message "LDAP Password:" appears if a wrong password has been
entered (this is correct and should happen). This is how I know the
LDAP lookups are functional. Also, finger from the server works

The functioning RedHat server uses the same versions of nss, pam, and
openssh listed below.

Software Versions:
SGI ProPack 2.3 for Linux, Build 230r11-0310072229
nss_ldap 215
pam_ldap 167
OpenSSh 3.7.1p2

SGI ProPack 2.3 for Linux, Build 230r11-0310072229
Kernel 2.4.21-sgi230r7 on an ia64

.edu login: aj8417

User not known to the underlying authentication module
Current /etc/pam.d/login file which works on a RedHat server is as

auth required /lib/security/pam_securetty.so
auth required /lib/security/pam_nologin.so
auth sufficient /lib/security/pam_stack.so service=system-auth
auth required /lib/security/pam_ldap.so try_first_pass
account required /lib/security/pam_stack.so service=system-auth
account required /lib/security/pam_access.so
accessfile=/etc/security/access.conf fieldsep=:
password required /lib/security/pam_stack.so service=system-auth
session required /lib/security/pam_stack.so service=system-auth
session required /lib/security/pam_mkhomedir.so skel=/etc/skel/
session optional /lib/security/pam_console.so

Any help would be appreciated.