Index: channel.c
===================================================================
--- channel.c	(revision 7436)
+++ channel.c	(working copy)
@@ -996,7 +996,22 @@
 		AST_LIST_HEAD_INIT_NOLOCK(&chan->spies->list);
 		AST_LIST_INSERT_HEAD(&chan->spies->list, spy, list);
 	} else {
-		AST_LIST_INSERT_TAIL(&chan->spies->list, spy, list);
+		do {
+			if ((&chan->spies->list)->first == (spy)) {
+				(&chan->spies->list)->first = (spy)->list.next;
+				if ((&chan->spies->list)->last == (spy))
+					(&chan->spies->list)->last = NULL;
+			} else {
+				struct ast_channel_spy *curelm = (&chan->spies->list)->first;
+				while (curelm && curelm->list.next != (spy))
+					curelm = curelm->list.next;
+				if (curelm) {
+					curelm->list.next = (spy)->list.next;
+					if ((&chan->spies->list)->last == (spy))
+						(&chan->spies->list)->last = curelm;
+				}
+			}
+		} while (0);
 	}
 
 	if (ast_test_flag(spy, CHANSPY_TRIGGER_MODE) != CHANSPY_TRIGGER_NONE) {
Index: include/asterisk/linkedlists.h
===================================================================
--- include/asterisk/linkedlists.h	(revision 7436)
+++ include/asterisk/linkedlists.h	(working copy)
@@ -381,7 +381,8 @@
   used to link entries of this list together.
 
   Note: The link field in the appended entry is \b not modified, so if it is
-  actually the head of a list itself, the entire list will be appended.
+  actually the head of a list itself, the entire list will be appended
+  temporarily (until the next AST_LIST_INSERT_TAIL is performed).
  */
 #define AST_LIST_INSERT_TAIL(head, elm, field) do {			\
       if (!(head)->first) {						\
@@ -428,11 +429,13 @@
 			(head)->last = NULL;			\
 	} else {								\
 		typeof(elm) curelm = (head)->first;			\
-		while (curelm->field.next != (elm))			\
+		while (curelm && curelm->field.next != (elm))		\
 			curelm = curelm->field.next;			\
-		curelm->field.next = (elm)->field.next;			\
-		if ((head)->last == curelm->field.next)			\
-			(head)->last = curelm;				\
+		if (curelm) { /* Found in list */			\
+			curelm->field.next = (elm)->field.next;		\
+			if ((head)->last == (elm))			\
+				(head)->last = curelm;			\
+		} /* else not found */					\
 	}								\
 } while (0)