diff -Nru luit-0.99.0.orig/configure.ac luit-0.99.0/configure.ac
--- luit-0.99.0.orig/configure.ac	2005-08-01 22:15:17 +0200
+++ luit-0.99.0/configure.ac	2005-08-13 16:46:26 +0200
@@ -38,7 +38,7 @@
 PKG_CHECK_MODULES(LUIT, x11 fontenc)
 
 case $host_os in
-    linux*)
+    linux* | freebsd*)
         OS_CFLAGS="-D_XOPEN_SOURCE"
         ;;
     *)