http://lists.samba.org/archive/samba-technical/2007-March/052606.html
http://websvn.samba.org/cgi-bin/viewcvs.cgi?view=rev&root=samba&rev=22015

--- samba-3.0.24/source/nsswitch/winbindd_ads.c	2007-02-05 03:59:14.000000000 +0900
+++ samba-3.0.24.osstech/source/nsswitch/winbindd_ads.c	2007-04-01 22:07:41.961733322 +0900
@@ -949,6 +949,8 @@ static NTSTATUS lookup_groupmem(struct w
 			if (num_retries < 5) {
 				num_retries++;
 				num_members = 0;
+				ads_msgfree(ads, res);
+				res = NULL;
 				continue;
 			} else {
 				DEBUG(5, ("ads: lookup_groupmem USN on this record changed"
@@ -964,6 +966,9 @@ static NTSTATUS lookup_groupmem(struct w
 						 &attrs[0],
 						 &num_members,
 						 &more_values);
+		
+	    	ads_msgfree(ads, res);
+	    	res = NULL;
 
 		if ((members == NULL) || (num_members == 0))
 			break;