Log entries like these look a bit suspicious:

4573:20100323:094536.265 In DCmass_add_history()
4573:20100323:094536.265 In DBget_maxid history_log.id
4573:20100323:094536.265 In DCget_nextid history_log.id [1]
4573:20100323:094536.265 End of DCget_nextid history_log.id [47796:47796]
4573:20100323:094536.265 Query [txnlev:1] [insert into history_log (id,itemid,clock,timestamp,source,severity,value,logeventid) values (47796,22815,1269330326,0,'',0,' "value":"\\t\\t\\t\\"value\\":
" 4573:20100323:094112.911 Query [txnlev:1] [update items set lastclock=1269330062,prevvalue=lastvalue,lastvalue=\'\\\\t\\\\t\\\\t\\\\\\"value\\\\\\":\\\\\\"\\\\\\\\\\\\\\\\t\\\\\\\\\\\\\\\\t\\\\\\\\\\\\\\\\t\\\\\\\\\\\\\\\\\\\\\\"value\\\\\\\\\\\\\\\\\\\\\\":\\\\\\\\\\\\\\\\\\\\\\"\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\t\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\t\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\t\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\"key\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\":\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\"log[{$SERVER_FILE},started]\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\",\\\\\\\\\\\\\\\\\\\\\\",\\\\\\",\',lastlogsize=6900130,mtime=0 where itemid=22815;
",",',0);