diff --git a/nest/proto.c b/nest/proto.c
index 99a4e85c..17155850 100644
--- a/nest/proto.c
+++ b/nest/proto.c
@@ -77,7 +77,7 @@ void *
 proto_new(struct proto_config *c, unsigned size)
 {
   struct protocol *pr = c->proto;
-  struct proto *p = mb_alloc(proto_pool, size);
+  struct proto *p = mb_allocz(proto_pool, size);
 
   p->cf = c;
   p->debug = c->debug;