diff --git a/attributs.py b/attributs.py
index 7b462a8..7c47e11 100644
--- a/attributs.py
+++ b/attributs.py
@@ -509,7 +509,7 @@ class dnsAttr(Attr):
     def parse_value(self, val):
         val = val.lower()
         name, _ = val.split('.', 1)
-        if not re.match('[a-z][-_a-z0-9]+', name):
+        if not re.match('[a-z](-*[a-z0-9]+)*', name):
             raise ValueError("Nom d'hote invalide %r" % val)
         self.value = val