diff --git a/thunderbird.spec b/thunderbird.spec
index 6a7c167..bbc3231 100644
--- a/thunderbird.spec
+++ b/thunderbird.spec
@@ -214,7 +214,7 @@ MOZ_OPT_FLAGS=$(echo "$RPM_OPT_FLAGS -fpermissive" | \
 %if %{?debug_build}
 MOZ_OPT_FLAGS=$(echo "$MOZ_OPT_FLAGS" | %{__sed} -e 's/-O2//')
 %endif
-%ifarch s390 s390x
+%ifarch s390
 MOZ_OPT_FLAGS=$(echo "$RPM_OPT_FLAGS" | %{__sed} -e 's/-g/-g1')
 %endif
 %ifarch s390 %{arm} ppc