diff --git a/library/GSUP_Types.ttcn b/library/GSUP_Types.ttcn
index 0d21404..7680815 100644
--- a/library/GSUP_Types.ttcn
+++ b/library/GSUP_Types.ttcn
@@ -79,8 +79,8 @@
 } with { variant "FIELDLENGTH(8)" };
 
 type enumerated GSUP_CancelType {
-	OSMO_GSUP_CANCEL_TYPE_UPDATE		(1),
-	OSMO_GSUP_CANCEL_TYPE_WITHDRAW		(2)
+	OSMO_GSUP_CANCEL_TYPE_UPDATE		(0),
+	OSMO_GSUP_CANCEL_TYPE_WITHDRAW		(1)
 } with { variant "FIELDLENGTH(8)" };
 
 type enumerated GSUP_CnDomain {