We have an old db (but an important one) running under an old Oracle version (7.3.4)*.
In the last days, we have problems with some tables (user tables related to application)
or system views (ex: v$datafile) :
The session freeze when operations** are done against theses tables/views
(there is no resource consumption, no log generated... : the only solution is to kill the session).
I used dbv to verify blocks : no block corruption…
We have the same problem when try to validate table structure with analyze command (session freeze).

* : we battled with direction to upgrade the Oracle version and the third party application (but as it is an application that will be replaced by a new one, we didn’t have the OK to do that).
** : operation such : select, drop (a user table), export, analyze ...

Any explanation or idea about this kind of problem ?