RFC5061 had changed the error cause codes for Dynamic Address
Reconfiguration As the following:
Cause Code
Value Cause Code
--------- ----------------
0x00A0 Request to Delete Last Remaining IP Address
0x00A1 Operation Refused Due to Resource Shortage
0x00A2 Request to Delete Source IP Address
0x00A3 Association Aborted Due to Illegal ASCONF-ACK
0x00A4 Request Refused - No Authorization