bump version number
diff --git a/configure.ac b/configure.ac
index eed4a84..12a1168 100644
--- a/configure.ac
+++ b/configure.ac
@@ -20,7 +20,7 @@
 AC_PREREQ(2.65)
 AC_CONFIG_MACRO_DIR([./aclocal])
 
-AC_INIT([thrift], [0.20.0])
+AC_INIT([thrift], [0.21.0])
 
 AC_CONFIG_AUX_DIR([.])