diff --git a/configure.in b/configure.in
index b0c3f8dc..c3c0af02 100644
--- a/configure.in
+++ b/configure.in
@@ -143,7 +143,7 @@ if test "$enable_client" = yes ; then
 		AC_CHECK_LIB(curses, tgetent, USE_TERMCAP_LIB=-lcurses,
 			AC_CHECK_LIB(termcap, tgetent, USE_TERMCAP_LIB=-ltermcap)))
 	AC_CHECK_LIB(readline, rl_callback_read_char, CLIENT_LIBS="-lreadline $CLIENT_LIBS $USE_TERMCAP_LIB",
-		AC_MSG_ERROR([[The client requires GNU readline library 4.0 or newer. Either install the library or use --disable-client to compile without the client.]]), $USE_TERMCAP_LIB)
+		AC_MSG_ERROR([[The client requires GNU readline library 2.1 or newer. Either install the library or use --disable-client to compile without the client.]]), $USE_TERMCAP_LIB)
 fi
 AC_SUBST(CLIENT)
 AC_SUBST(CLIENT_LIBS)