Trying this on Debian...and when connecting from MorphOS 3.6...
2014-07-06T21:15:54 WARNING: client "MorphOS" has incompatible version 1.4)
/tmp/buildd/synergy-1.3.8/src/lib/server/CClientProxyUnknown.cpp,248
EDIT:
I think I need to install a newer version on my Linux box.
EDIT #2:
Ok, upgrading Synergy on Debian to 1.4 gets it working but the key mapping is not working correctly at all... none of the keys are correct when I type.