diff --git a/sendmail.spec b/sendmail.spec
index f39d161..3a3671e 100644
--- a/sendmail.spec
+++ b/sendmail.spec
@@ -140,6 +140,10 @@ your sendmail.cf file.
 %patch13 -p1 -b .close_wait.p2
 %patch14 -p1 -b .fix_for_libbind
 
+# NOTE: on ppc64, the db4 library won't link with objects compiled
+# with the default ppc64 $RPM_OPT_FLAGS of '-m64' - disable for now,
+# but re-enable once db4 is fixed.
+
 %build
 # generate redhat config file
 cat > redhat.config.m4 << EOF
@@ -221,6 +225,13 @@ APPENDDEF(\`confLIBS',\`%{l_ldflags mysql .} -lmysqlclient -lz -lm')dnl
 EOF
 %endif
 
+# on s390x, we end up getting NAMED_BIND=1 but no -lbind ?!?!
+%ifarch s390x
+cat >> redhat.config.m4 << EOF
+APPENDDEF(\`confLIBS',\` -lbind')dnl
+EOF
+%endif
+
 DIRS="libsmutil sendmail mailstats rmail praliases smrsh makemap"
 
 %if "%{with_milter}" == "yes"