It's not possible to delegate rights to a *group* in scalix (at least that I could find yet, and I did look for it), but it's turns out you can delegate rights to *another account*:
Suppose you have an *account* called support on your server. You can then login via SWA (or OL) as support and *delegate* full rights to all those users in the "distribution group". In turn, each of those users can "add a mailbox* of the support account. That would allow each user on the "distribution group" to reply-to either as themselves or as the user who delegated the rights (support). This is a very elegant way to allow a user to have more than one reply address, as long as those replies are either standard or premium users on the same scalix server (as internet users is not possible)
The above takes care of your question.
You're now left with another problem: How to have an account called *support* on the server and at the same time forward a copy of any incoming email to other users on the "support distribution list" (not support *group*). Here is another post that explains how to do that using sxaa. That also means you'll have to remove your current group called "support":
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