Added subdomain delegation

src/hostinfo/named.py

@@ -127,6 +127,15 @@ def header(tree, domain, origin=None):
                 util.fqn(tree, ns._parent))
             pass
         pass
+    delegation = []
+    for ns in tree._host_._interface_._nameserver_:
+        subdomain = ns.domain[0].split('.')
+        if subdomain[1:] == domain.split('.'):
+            delegation.append( '%-16sIN      NS     %s' %
+                               (subdomain[0], util.fqn(tree, ns._parent)))
+
+    for d in sorted(delegation):
+        result += d
     result += ";"
     return result