I am using the latest version of (standalone) Jetpack (2.2.5). When I configure the Share buttons to be shown on Events, they do not appear. This is true on twenty-twelve theme with no other plugins activated.
Seems to work for me so long as I use the Default Events Template (Events > Settings > Template > Events Template) – if you are using a different template that might not be true.
ANYWAY – I think you need to mark this as an issue, but as far as I am concerned right now, I don’t need a fix. Once I saw it working, I realized that I need a different approach (i.e. add code to single event template) for my current design/situation.
OK, we’ll certainly look into it – there are limits to how far we can support integration with other plugins, even popular ones like Jetpack (especially as it does work under default circumstances – with a default theme and the default events template, for instance).
But we’ll definitely look at this and see what else we can do here.