I had new Application in 10g Rel2 into production where I am seeing blocking issue which will severely affect the application as it almost stopped working and here is what I can see in EM Session Session ID .......Wait Class Wait Event Blocked 3 111 Concurrency cursor:pin S wait on X 0 113 Concurrency Library cache load lock 0 119 Concurrency library cache load lock 0 133 Concurrency Library Cache Load Lock I have not set any _mutex variable and it is using default. Any suggestion TIA Sanjay --------------------------------- Yahoo! Messenger with Voice. Make PC-to-Phone Calls to the US (and 30+ countries) for 2¢/min or less.