--- chan_sip.c.orig	2003-12-18 21:09:56.000000000 -0500
+++ chan_sip.c	2003-12-18 21:14:52.000000000 -0500
@@ -52,6 +52,7 @@
 #include <netinet/in_systm.h>
 #include <netinet/ip.h>
 
+#define VIDEO_CODEC_MASK        0x1fc0000 // Video codecs from H.261 thru AST_FORMAT_MAX_VIDEO
 #ifndef IPTOS_MINCOST
 #define IPTOS_MINCOST 0x02
 #endif
@@ -1889,10 +1890,12 @@
 				while(*codecs && (*codecs < 33)) codecs++;
 			}
 		}
+		if (p->vrtp)
+			ast_rtp_pt_clear(p->vrtp);  // Must be cleared in case no m=video line exists
+
 		if (p->vrtp && (sscanf(m, "video %d RTP/AVP %n", &x, &len) == 1)) {
 			vportno = x;
 			// Scan through the RTP payload types specified in a "m=" line:
-			ast_rtp_pt_clear(p->vrtp);
 			codecs = m + len;
 			while(strlen(codecs)) {
 				if (sscanf(codecs, "%d%n", &codec, &len) != 1) {
@@ -2584,7 +2587,7 @@
 	strcat(m, "\r\n");
 	strcat(m2, "\r\n");
 	len = strlen(v) + strlen(s) + strlen(o) + strlen(c) + strlen(t) + strlen(m) + strlen(a);
-	if (p->vrtp)
+	if ((p->vrtp) && (p->jointcapability & VIDEO_CODEC_MASK)) // only if video response is appropriate
 		len += strlen(m2) + strlen(a2);
 	snprintf(costr, sizeof(costr), "%d", len);
 	add_header(resp, "Content-Type", "application/sdp");
@@ -2596,7 +2599,7 @@
 	add_line(resp, t);
 	add_line(resp, m);
 	add_line(resp, a);
-	if (p->vrtp) {
+	if ((p->vrtp) && (p->jointcapability & VIDEO_CODEC_MASK)) { // only if video response is appropriate
 		add_line(resp, m2);
 		add_line(resp, a2);
 	}