diff -rupN asterisk-1.6.0.2-orig/main/manager.c asterisk-1.6.0.2/main/manager.c
--- asterisk-1.6.0.2-orig/main/manager.c	2008-12-01 17:04:31.000000000 +0100
+++ asterisk-1.6.0.2/main/manager.c	2008-12-02 22:10:32.000000000 +0100
@@ -1729,7 +1729,7 @@ static int action_getvar(struct mansessi
 
 	if (varname[strlen(varname) - 1] == ')') {
 		if (!c) {
-			c = ast_channel_alloc(0, 0, "", "", "", "", "", 0, "Bogus/%p", SENTINEL);
+			c = ast_channel_alloc(0, 0, "", "", "", "", "", 0, "Bogus/%p", NULL);
 			if (c) {
 				ast_func_read(c, (char *) varname, workspace, sizeof(workspace));
 				ast_channel_free(c);