diff --git a/CHANGES b/CHANGES
index 37fecb8997..1ecb87cf49 100644
--- a/CHANGES
+++ b/CHANGES
@@ -1,3 +1,6 @@
+2586.	[bug]		Missing cleanup of SIG rdataset in searching a DLZ DB
+			or SDB. [RT #19577]
+
 2585.	[bug]		Uninitialized socket name could be referenced via a
 			statistics channel, triggering an assertion failure in
 			XML rendering. [RT #19427]
diff --git a/lib/dns/sdb.c b/lib/dns/sdb.c
index f141a102f2..a49357a288 100644
--- a/lib/dns/sdb.c
+++ b/lib/dns/sdb.c
@@ -15,7 +15,7 @@
  * PERFORMANCE OF THIS SOFTWARE.
  */
 
-/* $Id: sdb.c,v 1.66 2008/09/24 03:16:58 tbox Exp $ */
+/* $Id: sdb.c,v 1.67 2009/04/21 00:41:02 jinmei Exp $ */
 
 /*! \file */
 
@@ -880,9 +880,12 @@ find(dns_db_t *db, dns_name_t *name, dns_dbversion_t *version,
 				{
 					result = DNS_R_ZONECUT;
 					dns_rdataset_disassociate(rdataset);
-					if (sigrdataset != NULL)
+					if (sigrdataset != NULL &&
+					    dns_rdataset_isassociated
+						        (sigrdataset)) {
 						dns_rdataset_disassociate
 								(sigrdataset);
+					}
 				} else
 					result = DNS_R_DELEGATION;
 				break;
diff --git a/lib/dns/sdlz.c b/lib/dns/sdlz.c
index ec82c3e51c..b4099ed996 100644
--- a/lib/dns/sdlz.c
+++ b/lib/dns/sdlz.c
@@ -50,7 +50,7 @@
  * USE OR PERFORMANCE OF THIS SOFTWARE.
  */
 
-/* $Id: sdlz.c,v 1.18 2008/09/24 02:46:22 marka Exp $ */
+/* $Id: sdlz.c,v 1.19 2009/04/21 00:41:02 jinmei Exp $ */
 
 /*! \file */
 
@@ -844,9 +844,12 @@ find(dns_db_t *db, dns_name_t *name, dns_dbversion_t *version,
 				{
 					result = DNS_R_ZONECUT;
 					dns_rdataset_disassociate(rdataset);
-					if (sigrdataset != NULL)
+					if (sigrdataset != NULL &&
+					    dns_rdataset_isassociated
+					    		(sigrdataset)) {
 						dns_rdataset_disassociate
 							(sigrdataset);
+					}
 				} else
 					result = DNS_R_DELEGATION;
 				break;