Websocket functionality is currently implemented as a plugin. It should be part of Openfire's core feature set.
The code of the websocket plugin was merged with the master branch of the code (which will be Openfire 4.2.0), after a last update to the plugin was moved into the 4.1 branch. There, the current (and possibly last) release of the plugin lives: version 1.2.1. This version got a "priorToServerVersion" tag as introduced by OF-1353.
so openfire 4.2.1 direct support websocket