Peter Astrand says:

RedHat uses a patched version of OpenSSH, which always starts off
with calling PAM with bogus auth info. The idea is that successful
logins should take the same amount of time as unsuccessful logins. See
https://bugzilla.redhat.com/bugzilla/show_bug.cgi?id=101157. The problem
is that pam_mount catches the first (empty) password, and not the real
one. Thus, the mount fails.
                                                                                
I've found a solution to this problem: I've rearranged my system-auth
file like this:

auth  optional    /lib/security/pam_mount.so
auth  required    /lib/security/pam_env.so
auth  sufficient  /lib/security/pam_unix.so likeauth nullok use_first_pass
auth  required    /lib/security/pam_deny.so

Also, The smbmount program is unstable on RedHat 9: It hangs most of
the time.  This is due to NPTL. The solution is to add a mount wrapper
called mount.smbfs_no_nptl, and change pam_mount.conf to:
                                                                                
smbmount /bin/mount -t smbfs_no_nptl

See https://bugzilla.redhat.com/bugzilla/show_bug.cgi?id=103200 for
details. 
