I have updated the XIFF library to be compatible with BOSH 1.6. As SparkWeb is based on XIFF, most of the information here also applies to SparkWeb. Main good news are:
This updated version of XIFF will be fully compatible with the updated Openfire and Openfire's BOSH update will be included in version 3.6.x. However, there is an issue with Openfire versions released before the update.
According to XEP-0206, after a successful authentication, clients should send a body with xmpp:restart attribute set to true. But older Openfire versions do not recognize xmpp:restart, handling the request as if it was a polling request. Thus, it responds to the client after 30 seconds.
If you use the updated version of XIFF or SparkWeb with a version of Openfire that does not support BOSH 1.6 (i.e. lower than 3.6), please be aware that you will be experiencing a latency of 30 seconds during logins.