diff --git a/aclocal/ac_prog_bison.m4 b/aclocal/ac_prog_bison.m4
index c74b4f1..4d1198b 100644
--- a/aclocal/ac_prog_bison.m4
+++ b/aclocal/ac_prog_bison.m4
@@ -27,7 +27,7 @@
   if test "$bison_version" \< "$bison_required_version" ; then
     BISON=:
     AC_MSG_RESULT([no])
-    AC_MSG_ERROR([Bison version 2.4 or higher must be installed on the system!])
+    AC_MSG_ERROR([Bison version $bison_required_version or higher must be installed on the system!])
   else
     AC_MSG_RESULT([yes])
     BISON=bison