After upgrading to RH7.1 I found myself unable to use pam_userdb module: Jun 8 10:24:52 mojave snauth[1474]: PAM unable to dlopen(/lib/security/pam_userdb.so) Jun 8 10:24:52 mojave snauth[1474]: PAM [dlerror: /lib/security/pam_userdb.so: undefined symbol: conversation] Jun 8 10:24:52 mojave snauth[1474]: PAM adding faulty module: /lib/security/pam_userdb.so Recompiling the program (snauth) under RH7 didn't change anything.
This is a known PAM bug, see http://cvs.sourceforge.net/cgi-bin/viewcvs.cgi/pam/Linux-PAM/modules/pam_userdb/Makefile.diff?r1=1.3&r2=1.4 for a fix.
The newer pam-0.75 package in rawhide does not have this problem.