We have Oracle 9i R2 DB running on Windows 2000 server. I checked my alertSID.log and SIDSMON.log file and found the follwing lines of ORA error.

SMON: following errors trapped and ignored:
ORA-00604: error occurred at recursive SQL level 1
ORA-01001: invalid cursor
ORA-00601: cleanup lock conflict

Is this something serious about the DB. What needs to be done in order to getrid of these errors.