Index: main/callerid.c
===================================================================
--- main/callerid.c	(revision 410540)
+++ main/callerid.c	(working copy)
@@ -621,7 +621,7 @@
 				}
 				break;
 			case 5: /* Check checksum */
-				if (b != (256 - (cid->cksum & 0xff))) {
+				if (b + (cid->cksum & 0xff)) {
 					ast_log(LOG_NOTICE, "Caller*ID failed checksum\n");
 					/* Try again */
 					cid->sawflag = 0;