how to connect oracle reports to MS-sql server DB

Hi,
  I need to connect oracle reports 6i to MS-sql server-2000.oracle
reports is  in o/s windows2000 professional. I installed odbc driver,
created user DSN, tested. I'm able to connect from oracle sql plus to
sql server, but when im trying to connect from oracle
reports(username/[EMAIL PROTECTED]:dsn_name:databse), im geting error
"service handle not initialised'. How to solve this?