diff --git a/src/plugins/server/syntax.ml b/src/plugins/server/syntax.ml
index 41d2b8e45ff7f87c49d5a57afaeba5f623be4da6..f36e96261b9656876d2da94ac9ab8ace01f35f46 100644
--- a/src/plugins/server/syntax.ml
+++ b/src/plugins/server/syntax.ml
@@ -30,7 +30,7 @@ let check_plugin plugin name =
   let k = String.length plugin in
   if not (String.length name > k &&
           String.sub n 0 k = p &&
-          String.get n k = '.')
+          String.get n k = '-')
   then
     Senv.warning ~wkey:Senv.wpage
       "Data %S shall be named « %s-* »"