Call back button in the chat window

Hi.

I asterisk sends notification of missed calls from JID: asterisk @ domain.

I want to have in the chat window by pressing the button which might call this user.

Is this possible?

I suppose you mean to have this in Spark. Asterisk-IM itself is a dead project (nobody works on it for many years). Spark is nearly dead at the moment, so unless you hire a java programmer, who will program such behavior for you, not much can be done.