I'm afraid bounty alone won't help. There is just no traction with Spark among developers. There are hopes that moving to Git for source repository will sparkle a bit of interest. Not much so far (Openfire is seeing some more attention, but it was always a more active project).
For the xml corruption part i suggest using the latest 2.7.0 builds. After a 1.5 year of using it in production i didn't saw any history issue so far http://bamboo.igniterealtime.org/artifact/SPARK-INSTALL4J/shared/build-665/Insta ll4j/spark_2_7_0_665.exe
2. is probably easily doable, especially when Smack already supports it (Image may be NSFW.
Clik here to view.
SMACK-529), but someone has to step up. First, Spark should be adjusted for the newer Smack version. There were too many updates that can brake things.
4. seeing how things are with the voice chat and how complex all the Jitsi video bridge looks i somehow doubt it is doable in the near future.
5. There was a plugin for Spark. It has some quirks and it is not something outstanding, but it works Attaching it. Just rename to whiteboard and put into plugins folder in Spark. Then launch Spark and open chat with another user having this plugin. You will see two (should be one) additional buttons. It was produced by http://www.version2software.com/ maybe they can even share the source so it could be improved.
