Cabletron Systems SmartSwitch 9W006 User Manual page 279

C C T
AUSE ODES ABLE
Dec Value Hex Value Q.931 Cause
UNKNOWN Indicates that an event occurrent but that the network does not
provide causes for the actions that it takes, therefore the precise
nature of the event cannot be ascertained. This may, or may not,
indicate the occurrence of an error.
9W006 and 9W007 279