diff --git a/configure.ac b/configure.ac
index 373e2e0cef..696a50505f 100644
--- a/configure.ac
+++ b/configure.ac
@@ -1706,16 +1706,19 @@ if test x$CURL_DISABLE_LDAP != x1 ; then
 fi
 
 if test x$CURL_DISABLE_LDAP != x1 ; then
-  AC_CHECK_FUNCS([ldap_url_parse])
+  AC_CHECK_FUNCS([ldap_url_parse \
+                  ldap_init_fd])
 
   if test "$LDAPLIBNAME" = "wldap32"; then
     curl_ldap_msg="enabled (winldap)"
     AC_DEFINE(USE_WIN32_LDAP, 1, [Use Windows LDAP implementation])
   else
-    curl_ldap_msg="enabled (OpenLDAP)"
     if test "x$ac_cv_func_ldap_init_fd" = "xyes"; then
+      curl_ldap_msg="enabled (OpenLDAP)"
       AC_DEFINE(USE_OPENLDAP, 1, [Use OpenLDAP-specific code])
       AC_SUBST(USE_OPENLDAP, [1])
+    else
+      curl_ldap_msg="enabled (ancient OpenLDAP)"
     fi
   fi
 fi