UltraVNC

SSVNC seems to be what we are looking for I guess, as it seems to even have dsm support. However, a few quick tests and I still couldn't get it to work with the DSM plugin we use. I think the main issue is me not understanding how to use the ssvnc app to specificy username/password. It's kind of a ...

At work we use this plugin as well. I created a bug report (for Wine) for it a while ago but I don't think any developers really looked at it. I actually have a good idea of what the problem is with the old DSM plugin - which seems to be what you're using, as I had the same error message. See this ...