mutexes dbs_partn y pt_170005

Good morning, today we had the same problem like two days ago where batch processes working with a fragmented table are waiting for mutexes on one fragment with partnum 170005. We are using ids 10.FC9 on AIX 5.3. The processes with problems show like this: 7000004b39d9df0 S--PR-- 1266482 batch - 7000004b4fc1a90 0 4 878 0 7000004b39dac80 S--PR-- 1266983 batch - 7000004b4fc1a90 0 4 1423 2 The onstat -g wmx shows: Mutexes with waiters: mid addr name holder lkcnt waiter waittime 39153 7000004b29ab0b8 dbs_partn 1458478 0 1463345 0 40385 7000004b4fc1a90 pt_1700005 -1 0 1463394 0 1463347 0 1461865 0 1458891 0 The holder 1458478 is one batch process which too is having problems for the mutex. Two days ago i solved the problem running again update statistics medium for the table, this table is having statistics in medium mode since about 2 weeks, but we didnt have problems. The statistics running on this table before medium mode was on low mode. Im thinking to keep this table without distribution again, but i think this problem happened once when table didnt have statistics with distributions. Anyone knows why it could be this happening?? Thanks in advanced.