Have you used the facility before? If no then maybe smdr is not enabled....
the only other thing I can find is this from the help files.
SMDR error handling is limited to the recognition and reporting of clock malfunctions. In the event of a clock failure, the identity of the calling and called parties appears in the call record; however, the start time portion of the record remains blank and the call duration portion of the record contains the words "CLOCK MALFUNCTION" (columns 1 - 17). Any error other than a clock malfunction causes the SMDR output, and hence call record printing, to be inhibited.