diff --git a/configure.ac b/configure.ac
index df1f3c67..5ef51f2b 100644
--- a/configure.ac
+++ b/configure.ac
@@ -2,7 +2,7 @@
 # Process this file with autoconf to produce a configure script.
 #
 AC_PREREQ([2.67])
-AC_INIT([aria2],[1.18.3],[t-tujikawa@users.sourceforge.net],[aria2],[http://aria2.sourceforge.net/])
+AC_INIT([aria2],[1.18.4],[t-tujikawa@users.sourceforge.net],[aria2],[http://aria2.sourceforge.net/])
 
 AC_CANONICAL_HOST
 AC_CANONICAL_TARGET