diff --git a/acinclude.m4 b/acinclude.m4
index 70e2555f..ea8ec528 100644
--- a/acinclude.m4
+++ b/acinclude.m4
@@ -40,7 +40,7 @@ case "$host_os" in
         ;;
     esac
   ;;
-  freebsd* | netbsd* | openbsd*)
+  kfreebsd* | freebsd* | netbsd* | openbsd*)
     if echo __ELF__ | $CC -E - | grep __ELF__ > /dev/null; then
       objfmt='BSD-a.out'
     else