Although 8.1.7 does contain additional features than 8.1.6 it is essentially 8.1.6 with bug fixes:

Metalink Note - 120613.1

Oracle9i is very different from Oracle8i. You can look at some of the new features at:

http://www.oracle-base.com/Articles/9i/Articles9i.asp
http://otn.oracle.com/docs/products/...a96531/toc.htm
Metalink Note - 190190.1

Cheers