diff --git a/configure.ac b/configure.ac
index f445589..2b044f8 100644
--- a/configure.ac
+++ b/configure.ac
@@ -328,6 +328,9 @@ AC_ARG_ENABLE(manpages, AC_HELP_STRING([--enable-manpages],
 					[enable_manpages=${enableval}])
 if (test "${enable_manpages}" != "no"); then
 	AC_CHECK_PROGS(RST2MAN, [rst2man rst2man.py], "no")
+	if (test "${RST2MAN}" = "no" ); then
+		AC_MSG_ERROR([rst2man is required])
+	fi
 fi
 AM_CONDITIONAL(MANPAGES, test "${enable_manpages}" = "yes")
 AM_CONDITIONAL(RUN_RST2MAN, test "${enable_manpages}" = "yes" && test "${RST2MAN}" != "no")