Oracle Text, create index (indextype is ctxsys.context)

Question

Dear sirs,
I am a new user of Oracle Text (Oracle 11g release 11.2) and I am unable to create an index of type ctxsys.context). Any suggestions?:
code:
drop table mytable;
drop index myindex force;
create table mytable(id number primary key, docs clob);
insert into mytable values(111555,'this text will be indexed');
insert into mytable values(111556,'this is a default datastore example');
commit;
create index myindex on mytable(docs)
indextype is ctxsys.context
parameters ('DATASTORE CTXSYS.DEFAULT_DATASTORE');
+++++++
error messages:
create index myindex on mytable(docs)
ERROR at line 1:
ORA-29855: error occurred in the execution of ODCIINDEXCREATE routine
ORA-20000: Oracle Text error:
ORA-06508: PL/SQL: could not find program unit being called
ORA-06512: at "CTXSYS.DRUE", line 160
ORA-06512: at "CTXSYS.TEXTINDEXMETHODS", line 366

Answer 1

Please check for invalid objects. Log on as sys or system and run:
select owner, object_name, object_type from all_objects where status='INVALID';
Post the results here and we'll advise the next step.
If any objects owned by CTXSYS are invalid you may need to recompile the CTXSYS schema.