Welcome to the JSR 311 project at Java.net. This project is under the CDDL license. Here you'll find drafts of the API and specification along with mailing lists for communication with the expert group. Additional background information and formal milestone releases of the specification and API can be found on the JCP JSR 311 page.
Older drafts and API documentation can be found on the API history page.
The open source reference implementation is available as project Jersey