diff --git a/library/MNCC_EncDec.cc b/library/MNCC_EncDec.cc
index b4937e7..f2692d7 100644
--- a/library/MNCC_EncDec.cc
+++ b/library/MNCC_EncDec.cc
@@ -259,7 +259,7 @@
 	case MNCC_RTP_FREE:
 		in_rtp = (const struct gsm_mncc_rtp *) in_mncc;
 		rtp = MNCC__PDU__Rtp(in_rtp->callref, in_rtp->ip, in_rtp->port, in_rtp->payload_type,
-				     in_rtp->payload_msg_type);
+				     in_rtp->payload_msg_type, in_rtp->sdp);
 		u.rtp() = rtp;
 		break;
 	default:
@@ -315,6 +315,7 @@
 		sign.imsi() = CHARSTRING(in_mncc->imsi);
 		sign.lchan__type() = in_mncc->lchan_type;
 		sign.lchan__mode() = in_mncc->lchan_mode;
+		sign.sdp() = in_mncc->sdp;
 		u.signal() = sign;
 		break;
 	}
diff --git a/library/MNCC_Types.ttcn b/library/MNCC_Types.ttcn
index 828f341..5296579 100644
--- a/library/MNCC_Types.ttcn
+++ b/library/MNCC_Types.ttcn
@@ -360,7 +360,9 @@
 	charstring	imsi,
 
 	uint8_t		lchan_type,	/* empty in OSmoMSC */
-	uint8_t		lchan_mode	/* empty in OsmoMSC */
+	uint8_t		lchan_mode,	/* empty in OsmoMSC */
+
+	charstring	sdp optional
 };
 
 
@@ -374,7 +376,9 @@
 	uint32_t	ip,
 	uint16_t	rtp_port,
 	uint32_t	payload_type,
-	uint32_t	payload_msg_type
+	uint32_t	payload_msg_type,
+
+	charstring	sdp optional
 };
 
 type record MNCC_PDU_Hello {
@@ -464,7 +468,8 @@
 			emergency := omit,
 			imsi := "",
 			lchan_type := 0,
-			lchan_mode := 0
+			lchan_mode := 0,
+			sdp := ""
 		}
 	}
 }
@@ -494,7 +499,8 @@
 			emergency := *,
 			imsi := ?,
 			lchan_type := ?,
-			lchan_mode := ?
+			lchan_mode := ?,
+			sdp := *
 		}
 	}
 }
@@ -527,7 +533,8 @@
 			emergency := omit,
 			imsi := imsi,
 			lchan_type := 0,
-			lchan_mode := 0
+			lchan_mode := 0,
+			sdp := ""
 		}
 	}
 };
@@ -559,7 +566,8 @@
 			emergency := *,
 			imsi := imsi,
 			lchan_type := ?,
-			lchan_mode := ?
+			lchan_mode := ?,
+			sdp := *
 		}
 	}
 };
@@ -592,7 +600,8 @@
 			emergency := omit,
 			imsi := imsi,
 			lchan_type := 0,
-			lchan_mode := 0
+			lchan_mode := 0,
+			sdp := ""
 		}
 	}
 };
@@ -623,7 +632,8 @@
 			emergency := omit,
 			imsi := imsi,
 			lchan_type := ?,
-			lchan_mode := ?
+			lchan_mode := ?,
+			sdp := *
 		}
 	}
 };
@@ -656,7 +666,8 @@
 			emergency := *,
 			imsi := imsi,
 			lchan_type := ?,
-			lchan_mode := ?
+			lchan_mode := ?,
+			sdp := *
 		}
 	}
 }
@@ -688,7 +699,8 @@
 			emergency := omit,
 			imsi := imsi,
 			lchan_type := 0,
-			lchan_mode := 0
+			lchan_mode := 0,
+			sdp := ""
 		}
 	}
 }
@@ -719,7 +731,8 @@
 			emergency := omit,
 			imsi := "",
 			lchan_type := 0,
-			lchan_mode := 0
+			lchan_mode := 0,
+			sdp := ""
 		}
 	}
 }
@@ -750,7 +763,8 @@
 			emergency := *,
 			imsi := ?,
 			lchan_type := ?,
-			lchan_mode := ?
+			lchan_mode := ?,
+			sdp := *
 		}
 	}
 }
@@ -791,7 +805,8 @@
 			emergency := omit,
 			imsi := ?,
 			lchan_type := ?,
-			lchan_mode := ?
+			lchan_mode := ?,
+			sdp := *
 		}
 	}
 }
@@ -822,7 +837,8 @@
 			emergency := omit,
 			imsi := "",
 			lchan_type := 0,
-			lchan_mode := 0
+			lchan_mode := 0,
+			sdp := ""
 		}
 	}
 }
@@ -855,7 +871,8 @@
 			emergency := omit,
 			imsi := ?,
 			lchan_type := ?,
-			lchan_mode := ?
+			lchan_mode := ?,
+			sdp := *
 		}
 	}
 }
@@ -887,7 +904,8 @@
 			emergency := omit,
 			imsi := "",
 			lchan_type := 0,
-			lchan_mode := 0
+			lchan_mode := 0,
+			sdp := ""
 		}
 	}
 }
@@ -922,7 +940,8 @@
 			emergency := omit,
 			imsi := "",
 			lchan_type := 0,
-			lchan_mode := 0
+			lchan_mode := 0,
+			sdp := ""
 		}
 	}
 }
@@ -955,7 +974,8 @@
 			emergency := omit,
 			imsi := ?,
 			lchan_type := ?,
-			lchan_mode := ?
+			lchan_mode := ?,
+			sdp := *
 		}
 	}
 }
@@ -988,7 +1008,8 @@
 			emergency := omit,
 			imsi := "",
 			lchan_type := 0,
-			lchan_mode := 0
+			lchan_mode := 0,
+			sdp := ""
 		}
 	}
 }
@@ -1021,7 +1042,8 @@
 			emergency := omit,
 			imsi := "",
 			lchan_type := 0,
-			lchan_mode := 0
+			lchan_mode := 0,
+			sdp := ""
 		}
 	}
 }
@@ -1053,7 +1075,8 @@
 			emergency := omit,
 			imsi := ?,
 			lchan_type := ?,
-			lchan_mode := ?
+			lchan_mode := ?,
+			sdp := *
 		}
 	}
 }
@@ -1088,7 +1111,8 @@
 			emergency := *,
 			imsi := ?,
 			lchan_type := ?,
-			lchan_mode := ?
+			lchan_mode := ?,
+			sdp := *
 		}
 	}
 }
@@ -1120,7 +1144,8 @@
 			emergency := omit,
 			imsi := "",
 			lchan_type := 0,
-			lchan_mode := 0
+			lchan_mode := 0,
+			sdp := ""
 		}
 	}
 }
@@ -1152,7 +1177,8 @@
 			emergency := omit,
 			imsi := "",
 			lchan_type := 0,
-			lchan_mode := 0
+			lchan_mode := 0,
+			sdp := ""
 		}
 	}
 }
@@ -1183,7 +1209,8 @@
 			emergency := *,
 			imsi := ?,
 			lchan_type := ?,
-			lchan_mode := ?
+			lchan_mode := ?,
+			sdp := *
 		}
 	}
 }
@@ -1217,7 +1244,8 @@
 			emergency := *,
 			imsi := ?,
 			lchan_type := ?,
-			lchan_mode := ?
+			lchan_mode := ?,
+			sdp := *
 		}
 	}
 }
@@ -1249,7 +1277,8 @@
 			emergency := omit,
 			imsi := "",
 			lchan_type := 0,
-			lchan_mode := 0
+			lchan_mode := 0,
+			sdp := ""
 		}
 	}
 }
@@ -1283,7 +1312,8 @@
 			emergency := omit,
 			imsi := "",
 			lchan_type := 0,
-			lchan_mode := 0
+			lchan_mode := 0,
+			sdp := ""
 		}
 	}
 }
@@ -1316,7 +1346,8 @@
 			emergency := *,
 			imsi := ?,
 			lchan_type := ?,
-			lchan_mode := ?
+			lchan_mode := ?,
+			sdp := *
 		}
 	}
 }
@@ -1349,7 +1380,8 @@
 			emergency := *,
 			imsi := ?,
 			lchan_type := ?,
-			lchan_mode := ?
+			lchan_mode := ?,
+			sdp := *
 		}
 	}
 }
@@ -1381,7 +1413,8 @@
 			emergency := omit,
 			imsi := "",
 			lchan_type := 0,
-			lchan_mode := 0
+			lchan_mode := 0,
+			sdp := ""
 		}
 	}
 }
@@ -1413,7 +1446,8 @@
 			emergency := omit,
 			imsi := "",
 			lchan_type := 0,
-			lchan_mode := 0
+			lchan_mode := 0,
+			sdp := ""
 		}
 	}
 }
@@ -1443,7 +1477,8 @@
 			emergency := omit,
 			imsi := ?,
 			lchan_type := 0,
-			lchan_mode := 0
+			lchan_mode := 0,
+			sdp := ""
 		}
 	}
 }
@@ -1490,7 +1525,8 @@
 			emergency := omit,
 			imsi := "",
 			lchan_type := 0,
-			lchan_mode := 0
+			lchan_mode := 0,
+			sdp := ""
 		}
 	}
 }
@@ -1521,7 +1557,8 @@
 			emergency := *,
 			imsi := ?,
 			lchan_type := ?,
-			lchan_mode := ?
+			lchan_mode := ?,
+			sdp := *
 		}
 	}
 }
@@ -1552,7 +1589,8 @@
 			emergency := *,
 			imsi := ?,
 			lchan_type := ?,
-			lchan_mode := ?
+			lchan_mode := ?,
+			sdp := *
 		}
 	}
 }
@@ -1583,7 +1621,8 @@
 			emergency := omit,
 			imsi := "",
 			lchan_type := 0,
-			lchan_mode := 0
+			lchan_mode := 0,
+			sdp := ""
 		}
 	}
 }
@@ -1614,7 +1653,8 @@
 			emergency := omit,
 			imsi := "",
 			lchan_type := 0,
-			lchan_mode := 0
+			lchan_mode := 0,
+			sdp := ""
 		}
 	}
 }
@@ -1653,7 +1693,8 @@
 			emergency := *,
 			imsi := ?,
 			lchan_type := ?,
-			lchan_mode := ?
+			lchan_mode := ?,
+			sdp := *
 		}
 	}
 }
@@ -1684,7 +1725,8 @@
 			emergency := omit,
 			imsi := "",
 			lchan_type := 0,
-			lchan_mode := 0
+			lchan_mode := 0,
+			sdp := ""
 		}
 	}
 }
@@ -1715,7 +1757,8 @@
 			emergency := omit,
 			imsi := "",
 			lchan_type := 0,
-			lchan_mode := 0
+			lchan_mode := 0,
+			sdp := ""
 		}
 	}
 }
@@ -1747,7 +1790,8 @@
 			emergency := *,
 			imsi := ?,
 			lchan_type := ?,
-			lchan_mode := ?
+			lchan_mode := ?,
+			sdp := *
 		}
 	}
 }
@@ -1778,7 +1822,8 @@
 			emergency := omit,
 			imsi := "",
 			lchan_type := 0,
-			lchan_mode := 0
+			lchan_mode := 0,
+			sdp := ""
 		}
 	}
 }
@@ -1810,7 +1855,8 @@
 			emergency := omit,
 			imsi := "",
 			lchan_type := 0,
-			lchan_mode := 0
+			lchan_mode := 0,
+			sdp := ""
 		}
 	}
 }
@@ -1849,7 +1895,8 @@
 			emergency := omit,
 			imsi := "",
 			lchan_type := 0,
-			lchan_mode := 0
+			lchan_mode := 0,
+			sdp := ""
 		}
 	}
 }
@@ -1877,7 +1924,8 @@
 			ip := 0,
 			rtp_port := 0,
 			payload_type := 0,
-			payload_msg_type := 0
+			payload_msg_type := 0,
+			sdp := ""
 		}
 	}
 }
@@ -1897,7 +1945,8 @@
 			ip := ip,
 			rtp_port := rtp_port,
 			payload_type := payload_type,
-			payload_msg_type := ?
+			payload_msg_type := ?,
+			sdp := *
 		}
 	}
 }
@@ -1911,7 +1960,8 @@
 			ip := ip,
 			rtp_port := rtp_port,
 			payload_type := pt,
-			payload_msg_type := 0
+			payload_msg_type := 0,
+			sdp := ""
 		}
 	}
 }
@@ -1926,7 +1976,8 @@
 			ip := ip,
 			rtp_port := rtp_port,
 			payload_type := pt,
-			payload_msg_type := 0
+			payload_msg_type := 0,
+			sdp := ""
 		}
 	}
 }
diff --git a/library/mncc.h b/library/mncc.h
index 3e00db8..9aff948 100644
--- a/library/mncc.h
+++ b/library/mncc.h
@@ -265,6 +265,8 @@
 
 	unsigned char	lchan_type;
 	unsigned char	lchan_mode;
+
+	char		sdp[1024];
 };
 
 struct gsm_data_frame {
@@ -296,6 +298,8 @@
 	uint16_t	port;
 	uint32_t	payload_type;
 	uint32_t	payload_msg_type;
+
+	char		sdp[1024];
 };
 
 struct gsm_mncc_bridge {