how to change $ORACLE_HOME

I need to change the location of $ORACLE_HOME on some databases here. Here is how I think it can be done:

1. alter database backup controlfile to trace
2. shutdown db
3. remove existing control files
4. change $ORACLE_HOME in PFILE and CONFIG file
5. change $ORACLE_HOME in ORATAB
6. set ORACLE_HOME to new location in environment (. oraenv)
7. start SQLDBA and execute previous trace file to produce new control files;

I have tried this once and it worked OK. Now when I do this I get the following errors when executing the script to produce the new control files.

  ORACLE instance started.
  ORA-01503: CREATE CONTROLFILE failed
  ORA-01565: error in identifying file
  '/database/system/PROD/system.dbf'
  ORA-09782: sfifi: another instance has the same database mounted.   ORA-01507: database not mounted

Could someone please outline the necessary procedure and let me know what I am doing wrong ?

Thanks

Nick

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+    Nick Price                               Technical Consultant             +

+    Internet: nprice_at_7-Eleven.com            Hong Kong Convenience Stores Ltd.+

+    Tel     : +852 2802 6869                 North Point                      +


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