Hello,
some Snap-Ins are not supported anymore, like the Smart Caller ID.
Will there be a Breeze API which can handle these types of requests (getting a callers phone number before it reaches the called party and manipulate the SIP protocol)?

Thanks.

What specific functionality of Smart CallerID are you referring to? Breeze itself is also end of sale unless it is used with Oceana snap-ins, so I am not sure how much value there is in fully answering your question. I would anticipate you could build a replacement for the service out of a SIP trunking service conneced to Session Manager, but obviously that is more work than it used to be.

Correct me if I'm wrong, but Breeze is still needed for Presence (even in Release 10.x).
I heard rumors about new APIs centralized in Breeze for the Aura Systems.
Will there be a (easy?) way to read and modify the SIP messages a client receives?

You are right, but Presence+Breeze should be viewed as a standalone product. You can not add other applications to the Breeze cluster hosting Presence.

As to what Avaya is cooking up, I have not seen everything that is in the kitchen, but at the moment I have not seen a replacement for SIP header manipulation/filtering. DevConnect focuses on what has gone (or will shortly go) GA. We don't have the time to do a lot of looking at the product roadmaps.