diff --git a/NEWS b/NEWS
index a6b2a4316..19b0ac6fb 100644
--- a/NEWS
+++ b/NEWS
@@ -1,3 +1,7 @@
+New in spot 1.99.3a (not yet released)
+
+  Nothing yet.
+
 New in spot 1.99.3 (2015-08-26)
 
   * The CGI script for LTL translation offers a HOA download link
diff --git a/configure.ac b/configure.ac
index 66ca42182..aeed5e8b2 100644
--- a/configure.ac
+++ b/configure.ac
@@ -21,7 +21,7 @@
 # along with this program.  If not, see <http://www.gnu.org/licenses/>.
 
 AC_PREREQ([2.61])
-AC_INIT([spot], [1.99.3], [spot@lrde.epita.fr])
+AC_INIT([spot], [1.99.3a], [spot@lrde.epita.fr])
 AC_CONFIG_AUX_DIR([tools])
 AC_CONFIG_MACRO_DIR([m4])
 AM_INIT_AUTOMAKE([1.11 gnu tar-ustar color-tests parallel-tests])