Set the soname which glibc expects us to have.
--- nss_ldap-254/configure.in	2007-02-26 16:40:53.000000000 -0500
+++ nss_ldap-254/configure.in	2007-02-26 16:40:47.000000000 -0500
@@ -92,7 +92,7 @@
   nss_ldap_so_LDFLAGS="-b -dynamic -G `cat exports.hpux`"
   CPPFLAGS="$CPPFLAGS -I. -DHPUX"
   TARGET_OS=HPUX ;;
-linux*) nss_ldap_so_LDFLAGS="-shared -Wl,-Bdynamic -Wl,--version-script,\$(srcdir)/exports.linux" ;;
+linux*) nss_ldap_so_LDFLAGS="-shared -Wl,-Bdynamic -Wl,--version-script,\$(srcdir)/exports.linux -Wl,-soname=libnss_ldap.so.2" ;;
 *) nss_ldap_so_LDFLAGS="-shared -Wl,-Bdynamic" ;;
 esac