More than one ST label in calblock, more than one BB label etc.

[michaelaye]

Check if these cases are safe:

INFO:diviner.calib:Found more than one BB label in CalBlock at 2013-03-05 10:22:37.911000.
INFO:diviner.calib:Found more than one BB label in CalBlock at 2013-03-05 11:16:48.148000.
INFO:diviner.calib:Found more than one ST label in CalBlock at 2013-03-17 23:45:45.451000.