diff --git a/configure.ac b/configure.ac
index 566ddcb..2ba68b6 100644
--- a/configure.ac
+++ b/configure.ac
@@ -359,6 +359,7 @@ case $host_cpu in
 	;;
 esac
 AC_SUBST(GLX_ARCH_DEFINES)
+AC_SUBST([SYS_LIBS])
 
 dnl BSD *_video.c selection
 AM_CONDITIONAL(ALPHA_VIDEO, [test "x$ALPHA_VIDEO" = xyes])