diff --git a/src/m4/ax_boost_base.m4 b/src/m4/ax_boost_base.m4
index 4f93a0e09..e025a7e1c 100644
--- a/src/m4/ax_boost_base.m4
+++ b/src/m4/ax_boost_base.m4
@@ -92,7 +92,10 @@ if test "x$want_boost" = "xyes"; then
     libsubdirs="lib"
     ax_arch=`uname -m`
     case $ax_arch in
-      x86_64|ppc64|s390x|sparc64|aarch64)
+      x86_64)
+        libsubdirs="lib64 libx32 lib lib64"
+        ;;
+      ppc64|s390x|sparc64|aarch64)
         libsubdirs="lib64 lib lib64"
         ;;
     esac