Retroshare seems a nice software but we cannot consider including it in Tails unless it's packaged in Debian. By the way, I'm pretty sure we won't use it to replace Pidgin and Claws Mail but maybe provide it in addition to them...

That is not an official Debian package and in that sense it won't benefit from the many advantages of a real inclusion in Debian, which makes it otherwise non-sustainable for us to include such packages:

• be under the scrutiny of the Debian community
• provide OpenPGP signed packages
• follow the Debian process for security updates and new versions

But if Retroshare already proposes a non-official Debian package, maybe they are not so far from having it into Debian. You could check with them if that is in their plan.