diff -urN libnids-1.18/src/killtcp.c libnids-1.18.new/src/killtcp.c
--- libnids-1.18/src/killtcp.c	2002-08-21 18:19:40.000000000 +0200
+++ libnids-1.18.new/src/killtcp.c	2010-03-27 13:44:59.000000000 +0100
@@ -100,6 +100,6 @@
     if (initialized)
 	abort();
 }
-#elif
+#else
 #error Something wrong with LIBNET_VER
 #endif