diff -u -r1.677 chan_sip.c
--- chan_sip.c	17 Mar 2005 23:03:07 -0000	1.677
+++ chan_sip.c	20 Mar 2005 02:56:46 -0000
@@ -8436,9 +8437,9 @@
 		} else {
 			/* Initialize tag */	
 			p->tag = rand();
-			if (!strcmp(get_header(req, "Accept"), "application/dialog-info+xml"))
+			if (strcasestr(get_header(req, "Accept"), "application/dialog-info+xml")) {
 				p->subscribed = 2;
-			else if (!strcmp(get_header(req, "Accept"), "application/simple-message-summary")) {
+			} else if (strcasestr(get_header(req, "Accept"), "application/simple-message-summary")) {
 				/* Looks like they actually want a mailbox */
 
 				/* At this point, we should check if they subscribe to a mailbox that
@@ -8465,8 +8466,13 @@
 					ast_set_flag(p, SIP_NEEDDESTROY);	
 				}
 				return 0;
-			} else
+			} else if (strcasestr(get_header(req, "Accept"), "application/xpidf+xml")) {
 				p->subscribed = 1;
+			} else {
+				p->subscribed = 0;
+				transmit_response(p, "489 Bad Event", req);
+				ast_set_flag(p, SIP_NEEDDESTROY);	
+			}
 			if (p->subscribed)
 				p->stateid = ast_extension_state_add(p->context, p->exten, cb_extensionstate, p);
 		}