diff --git a/src/capisuite-py/consts.py b/src/capisuite-py/consts.py
index 5f44ff8..520d757 100644
--- a/src/capisuite-py/consts.py
+++ b/src/capisuite-py/consts.py
@@ -24,13 +24,10 @@ __known_sections__ = ('GLOBAL',
                       'MailFaxReceived',
                       'MailVoiceReceived')
 
-# capi return codes:
-# 34D8 = Incompatible destination
-
 # returncodes from call_voice and call_faxG3
 CONNECTION_ESTABLISHED = 0
 CONNECTION_TIMEOUT_EXCEEDED = 1
-CONNECTION_FAILED_UNKNONW_REASON = 2
+CONNECTION_FAILED_UNKNOWN_REASON = 2
 
 """
 reject causes:
@@ -39,6 +36,84 @@ reject causes:
   3 = user busy
   7 = incompatible destination
   8 = destination out of order
-  0x34A9 = temporary failure
-  0x3492 = no connection???
 """
+
+# For more detials about the error messaged please refere to 
+# http://www.capisuite.de/manual/apb.html
+
+error_messages = {
+    0x0000: "Normal call clearing, no error",
+    
+    # Protocol errors
+    0x3301: "Protocol error layer 1 (broken line or B-channel removed by signalling protocol)",
+    0x3302: "Protocol error layer 2",
+    0x3303: "Protocol error layer 3",
+    0x3304: "Another application got that call",
+
+    # these are T.30 (fax) errors
+    0x3311: "Fax-Error: Remote station is not a G3 fax device",
+    0x3312: "Fax-Error: Training error",
+    0x3313: "Fax-Error: Remote station doesn't support transfer mode, e.g. wrong resolution",
+    0x3314: "Fax-Error: Remote abort",
+    0x3315: "Fax-Error: Remote procedure error",
+    0x3316: "Fax-Error: Local transmit data underflow",
+    0x3317: "Fax-Error: Local receive data overflow",
+    0x3318: "Fax-Error: Local abort",
+    0x3319: "Fax-Error: Illegal parameter coding (e.g. defective SFF file)",
+    
+    # ISDN error codes
+    0x3400: "Normal termination, no reason available",
+    0x3480: "Normal termination",
+    0x3481: "Unallocated (unassigned) number",
+    0x3482: "No route to specified transit network",
+    0x3483: "No route to destination",
+    0x3486: "Channel unacceptable",
+    0x3487: "Call awarded and being delivered in an established channel",
+    0x3490: "Normal call clearing",
+    0x3491: "User busy",
+    0x3492: "No user responding",
+    0x3493: "No answer from user (user alerted)",
+    0x3495: "Call rejected",
+    0x3496: "Number changed",
+    0x349A: "Non-selected user clearing",
+    0x349B: "Destination out of order",
+    0x349C: "Invalid number format",
+    0x349D: "Facility rejected",
+    0x349E: "Response to STATUS ENQUIRY",
+    0x349F: "Normal, unspecified",
+    0x34A2: "No circuit / channel available",
+    0x34A6: "Network out of order",
+    0x34A9: "Temporary failure",
+    0x34AA: "Switching equipment congestion",
+    0x34AB: "Access information discarded",
+    0x34AC: "Requested circuit / channel not available",
+    0x34AF: "Resources unavailable, unspecified",
+    0x34B1: "Quality of service unavailable",
+    0x34B2: "Requested facility not subscribed",
+    0x34B9: "Bearer capability not authorized",
+    0x34BA: "Bearer capability not presently available",
+    0x34BF: "Service or option not available, unspecified",
+    0x34C1: "Bearer capability not implemented",
+    0x34C2: "Channel type not implemented",
+    0x34C5: "Requested facility not implemented",
+    0x34C6: "Only restricted digital information bearer capability is available",
+    0x34CF: "Service or option not implemented, unspecified",
+    0x34D1: "Invalid call reference value",
+    0x34D2: "Identified channel does not exist",
+    0x34D3: "A suspended call exists, but this call identity does not",
+    0x34D4: "Call identity in use",
+    0x34D5: "No call suspended",
+    0x34D6: "Call having the requested call identity has been cleared",
+    0x34D8: "Incompatible destination",
+    0x34DB: "Invalid transit network selection",
+    0x34DF: "Invalid message, unspecified",
+    0x34E0: "Mandatory information element is missing",
+    0x34E1: "Message type non-existent or not implemented",
+    0x34E2: "Message not compatible with call state or message type non-existent or not implemented",
+    0x34E3: "Information element non-existent or not implemented",
+    0x34E4: "Invalid information element contents",
+    0x34E5: "Message not compatible with call state",
+    0x34E6: "Recovery on timer expiry",
+    0x34EF: "Protocol error, unspecified",
+    0x34FF: "Interworking, unspecified",
+    }