Index: apps/app_stack.c
===================================================================
--- apps/app_stack.c	(revision 244242)
+++ apps/app_stack.c	(working copy)
@@ -346,7 +346,8 @@
 	AST_LIST_HEAD(, gosub_stack_frame) *oldlist;
 	struct gosub_stack_frame *newframe;
 	char argname[15], *tmp = ast_strdupa(data), *label, *endparen;
-	int i;
+	const char *prev_argc;
+	int i, max_argc = 0;
 	AST_DECLARE_APP_ARGS(args2,
 		AST_APP_ARG(argval)[100];
 	);
@@ -412,14 +413,25 @@
 		return -1;
 	}
 
+	ast_channel_lock(chan);
+	if ((prev_argc = pbx_builtin_getvar_helper(chan, "~ARGC~"))) {
+		max_argc = atoi(prev_argc);
+	}
+	ast_channel_unlock(chan);
+	if (args2.argc > max_argc) {
+		max_argc = args2.argc;
+	}
+
 	/* Now that we know for certain that we're going to a new location, set our arguments */
-	for (i = 0; i < args2.argc; i++) {
+	for (i = 0; i < max_argc; i++) {
 		snprintf(argname, sizeof(argname), "ARG%d", i + 1);
-		frame_set_var(chan, newframe, argname, args2.argval[i]);
-		ast_debug(1, "Setting '%s' to '%s'\n", argname, args2.argval[i]);
+		frame_set_var(chan, newframe, argname, i < args2.argc ? args2.argval[i] : "");
+		ast_debug(1, "Setting '%s' to '%s'\n", argname, i < args2.argc ? args2.argval[i] : "");
 	}
 	snprintf(argname, sizeof(argname), "%d", args2.argc);
 	frame_set_var(chan, newframe, "ARGC", argname);
+	snprintf(argname, sizeof(argname), "%d", max_argc);
+	frame_set_var(chan, newframe, "~ARGC~", argname);
 
 	/* And finally, save our return address */
 	oldlist = stack_store->data;