i did consider that, thats why the Q "why any user session will have exclusive locks on sys owned objects".. why anyone would re-complie a sys package unless there is a upgrade, re-run catalog (even this why anyone would like to do?).. recompile of packages will be done only when its invalid, but why would such a package go invalid?..

in a prd environment, such things on SYS schema is hardly done.

- Abhay.