diff --git a/library/GSM_RR_Types.ttcn b/library/GSM_RR_Types.ttcn
index e54bc92..2c607a7 100644
--- a/library/GSM_RR_Types.ttcn
+++ b/library/GSM_RR_Types.ttcn
@@ -113,6 +113,26 @@
 		INTERSYS_TO_EUTRAN_HO_CMD	('01100110'B)
 	} with { variant "FIELDLENGTH(8)" };
 
+	type enumerated RR_Cause {
+		GSM48_RR_CAUSE_NORMAL		('00'O),
+		GSM48_RR_CAUSE_ABNORMAL_UNSPEC	('01'O),
+		GSM48_RR_CAUSE_ABNORMAL_UNACCT	('02'O),
+		GSM48_RR_CAUSE_ABNORMAL_TIMER	('03'O),
+		GSM48_RR_CAUSE_ABNORMAL_NOACT	('04'O),
+		GSM48_RR_CAUSE_PREMPTIVE_REL	('05'O),
+		GSM48_RR_CAUSE_HNDOVER_IMP	('08'O),
+		GSM48_RR_CAUSE_CHAN_MODE_UNACCT	('09'O),
+		GSM48_RR_CAUSE_FREQ_NOT_IMPL	('0a'O),
+		GSM48_RR_CAUSE_CALL_CLEARED	('41'O),
+		GSM48_RR_CAUSE_SEMANT_INCORR	('5f'O),
+		GSM48_RR_CAUSE_INVALID_MAND_INF ('60'O),
+		GSM48_RR_CAUSE_MSG_TYPE_N	('61'O),
+		GSM48_RR_CAUSE_MSG_TYPE_N_COMPAT('62'O),
+		GSM48_RR_CAUSE_COND_IE_ERROR	('64'O),
+		GSM48_RR_CAUSE_NO_CELL_ALLOC_A	('65'O),
+		GSM48_RR_CAUSE_PROT_ERROR_UNSPC ('6f'O)
+	} with { variant "FIELDLENGTH(8)" };
+
 	type octetstring RestOctets  with { variant "PADDING(yes), PADDING_PATTERN('00101011'B)" };
 	type hexstring GsmBcdString with { variant "HEXORDER(low)" };
 	type GsmBcdString BcdMccMnc with { variant "FIELDLENGTH(6)" };