As of this writing, no correct, detailed instructions exist for integrating the WebSphere plugin in to Oracle iPlanet Web Server 7.
iPlanet, originally a Netscape product, was acquired by Sun and renamed SunOne Web Server, and later Java System Web Server. After Sun was acquired by Oracle, the product was renamed to Oracle iPlanet Web Server.
WebSphere refers to iPlanet by the older name, SunOne Web Server, and the native integration scripts do not work correctly, necessitating a manual configuration (see procedure below). Once configured, the pluging works as expected.