Whenever I try to connect to a Oracle 10g Database on my machine, I encountered this error message: ORA-01882: timezone region not found. This was true for SQl plus as well as while connecting using JDBC. The problem was Oracle 10g did not have "Asia/Kolkata" as a timezone region in the V$TIMEZONE_NAMES view. My machine however was configured to use the above timezone. When I changed the timezone to "Asia/Calcutta" on my machine, things started working fine. Little did the residents of Kolkata realize that changing the name of their city from Calcutta to Kolkata would have such implications!!! While most software has already started using the new name along with the old name, there are some old software that still does not support the new name. Of course, we can configure oracle to use the new name as well..