diff -urp bind-9.3.3/lib/dns/resolver.c bind-9.3.4/lib/dns/resolver.c
--- bind-9.3.3/lib/dns/resolver.c	2006-08-31 05:57:11.000000000 +0200
+++ bind-9.3.4/lib/dns/resolver.c	2007-01-11 06:05:10.000000000 +0100
@@ -218,6 +218,11 @@ struct fetchctx {
 	dns_name_t 			nsname; 
 	dns_fetch_t *			nsfetch;
 	dns_rdataset_t			nsrrset;
+
+	/*%
+	 * Number of queries that reference this context.
+	 */
+	unsigned int			nqueries;
 };
 
 #define FCTX_MAGIC			ISC_MAGIC('F', '!', '!', '!')
@@ -515,6 +524,9 @@ resquery_destroy(resquery_t **queryp) {
 
 	INSIST(query->tcpsocket == NULL);
 
+	query->fctx->nqueries--;
+	if (SHUTTINGDOWN(query->fctx))
+		maybe_destroy(query->fctx);	/* Locks bucket. */
 	query->magic = 0;
 	isc_mem_put(query->mctx, query, sizeof(*query));
 	*queryp = NULL;
@@ -1088,6 +1102,7 @@ fctx_query(fetchctx_t *fctx, dns_adbaddr
 	}
 
 	ISC_LIST_APPEND(fctx->queries, query, link);
+	query->fctx->nqueries++;
 
 	return (ISC_R_SUCCESS);
 
@@ -1540,7 +1555,7 @@ fctx_finddone(isc_task_t *task, isc_even
 			want_done = ISC_TRUE;
 		}
 	} else if (SHUTTINGDOWN(fctx) && fctx->pending == 0 &&
-		   ISC_LIST_EMPTY(fctx->validators)) {
+		   fctx->nqueries == 0 && ISC_LIST_EMPTY(fctx->validators)) {
 		bucketnum = fctx->bucketnum;
 		LOCK(&res->buckets[bucketnum].lock);
 		/*
@@ -2394,8 +2409,8 @@ fctx_destroy(fetchctx_t *fctx) {
 	REQUIRE(ISC_LIST_EMPTY(fctx->finds));
 	REQUIRE(ISC_LIST_EMPTY(fctx->altfinds));
 	REQUIRE(fctx->pending == 0);
-	REQUIRE(ISC_LIST_EMPTY(fctx->validators));
 	REQUIRE(fctx->references == 0);
+	REQUIRE(ISC_LIST_EMPTY(fctx->validators));
 
 	FCTXTRACE("destroy");
 
@@ -2569,7 +2584,7 @@ fctx_doshutdown(isc_task_t *task, isc_ev
 	}
 
 	if (fctx->references == 0 && fctx->pending == 0 &&
-	    ISC_LIST_EMPTY(fctx->validators))
+	    fctx->nqueries == 0 && ISC_LIST_EMPTY(fctx->validators))
 		bucket_empty = fctx_destroy(fctx);
 
 	UNLOCK(&res->buckets[bucketnum].lock);
@@ -2610,6 +2625,7 @@ fctx_start(isc_task_t *task, isc_event_t
 		 * pending ADB finds and no pending validations.
 		 */
 		INSIST(fctx->pending == 0);
+		INSIST(fctx->nqueries == 0);
 		INSIST(ISC_LIST_EMPTY(fctx->validators));
 		if (fctx->references == 0) {
 			/*
@@ -2771,6 +2787,7 @@ fctx_create(dns_resolver_t *res, dns_nam
 	fctx->restarts = 0;
 	fctx->timeouts = 0;
 	fctx->attributes = 0;
+	fctx->nqueries = 0;
 
 	dns_name_init(&fctx->nsname, NULL);
 	fctx->nsfetch = NULL;
@@ -6371,7 +6407,8 @@ dns_resolver_destroyfetch(dns_fetch_t **
 		/*
 		 * No one cares about the result of this fetch anymore.
 		 */
-		if (fctx->pending == 0 && ISC_LIST_EMPTY(fctx->validators) &&
+		if (fctx->pending == 0 && fctx->nqueries == 0 &&
+		    ISC_LIST_EMPTY(fctx->validators) &&
 		    SHUTTINGDOWN(fctx)) {
 			/*
 			 * This fctx is already shutdown; we were just