diff --git a/NEWS b/NEWS
index 51f21dd..a063499 100644
--- a/NEWS
+++ b/NEWS
@@ -1,5 +1,8 @@
 Copyright (C) 2014 Tim Rühsen
 
+03.08.2014 Release V0.5.1
+  * fix ASCII check for architectures where char <> signed char
+
 02.07.2014 Release V0.5.0
   * added configure --enable-runtime to allow for IDNA library
     selection as runtime dependency
diff --git a/configure.ac b/configure.ac
index 9419f8d..67d83d9 100644
--- a/configure.ac
+++ b/configure.ac
@@ -1,5 +1,5 @@
 
-AC_INIT([libpsl], [0.5.0], [tim.ruehsen@gmx.de], [libpsl], [http://github.com/rockdaboot/libpsl])
+AC_INIT([libpsl], [0.5.1], [tim.ruehsen@gmx.de], [libpsl], [http://github.com/rockdaboot/libpsl])
 AC_PREREQ([2.59])
 AM_INIT_AUTOMAKE([1.10 -Wall no-define foreign])
 
@@ -63,7 +63,7 @@ AS_IF([ test "$enable_man" != no ], [
 # 4. If any interfaces have been added, removed, or changed since the last update, increment current, and set revision to 0.
 # 5. If any interfaces have been added since the last public release, then increment age.
 # 6. If any existing interfaces have been removed or changed since the last public release, then set age to 0. 
-AC_SUBST([LIBPSL_SO_VERSION], [2:1:2])
+AC_SUBST([LIBPSL_SO_VERSION], [2:2:2])
 AC_SUBST([LIBPSL_VERSION], $VERSION)
 
 # Check for enable/disable builtin PSL data