The lifecycle policy for all Oracle Server releases, where lifecycle is defined as the length of support by development, is 21 months for all non-terminal releases and 27 months for all terminal releases. All desupport dates adhere to this policy. These dates may move out, however, based on business need, product interdependencies, etc.
Oracle 8.1.7 is the terminal release for Oracle 8i. Extended Assistance Support is till 31-dec-2003.
BTW, as you are in CA you could as well call them up and get more detailed info.