I was able to downgrade from 8.1.5 to 8.0.5 and able to bring up the database.
But when I tried "sqlplus system/manager"
I am getting following error..
Error accessing package DBMS_APPLICATION_INFO
ORA-00604: error occurred at recursive SQL level 1
ORA-01653: unable to extend table SYS.IDL_UB1$ by 15 in tablespace SYSTEM
Please let me know how can I resolve this problem.
Do you have enough free space in system or not ? Check and give a try.
Did you try compiling the system and sys invalid packages after downgrading ? If not try compiling 'em and see that helps.
How about running the down graded version of catalog and catproc ? IAM NOT SURE. Just an idea that strike my mind.
Yes, you are right, that was a space problem.