From their site: hi5 is a global brand for young people, where over 50 million members have established accounts and personal pages. We have a full SOAP API, and even a few REST endpoints.
Click the "Track this API" button on any profile page and never miss an API update, new app, or breaking news for that API again.
There are no source code libraries or how-to links for Hi5. If you know one why not add it?
How R U?