After 1.7, synergy pro moved to openssl rather than their own bespoke solution of the earlier builds because I guess nick bolton realized that openssl would do it better than he could.
As your served a ns.so plugin file when you register a client as part of the pro features enablement, that would have to be ppc binary compatible too. I haven't looked much at it since I got 1.7.2 working as ssl wrapped on gentoo, its a bit of a chore to get admin rights on some of the machines it controls to do upgrades for the sake of it.
But completely understood on the spare time to play with things...

Probably I can delve round with ssh and create a tunnel and do it the original way before pro came along, but if a later version of synergys has enabled mixed ssl and non ssl clients on the same lan (1.7.2 won't let *any* clients connect if a non ssl enabled one attempts to connect with the server in ssl mode, it effectively DOS's the synergys) then I'll probably just live with morphos client keystrokes being open on the local lan.