hi niels and alan, 

+verbatim+
toolsvc.muidsegmentregionrecoverytool             warning failed to find prds in main sector: 12
-verbatim-
was shown 37 times for 1582 events. 
/afs/cern.ch/user/g/gencomm/w0/oda/v36/data11_7tev.00187501.physics_jettauetmiss.merge.raw.v36.recon.task._lb0050._sfo-10._0001.job.tmp.log.1
please have a look. 

cheers, 
susumu 