Hi,
Someone please correct me if I'm wrong, but IIRC the managesieve interfaces of Roundcube and Thunderbird only allow you to choose between existing sieve scripts that are already available through the managesieve server. They *don't* provide an interface for constructing sieve scripts in the first place-- you still have to write them by hand.
sorry, I have to correct you:
With RoundCube 0.3 and the managesieve-plugin, you get an interface to click the rules you want to apply:
OK, good. I'm glad to be corrected, that is starting to look promising.
Compare http://www.horde.org/ingo/screenshots/rule.png . For now, ingo still appears to be more capable-- e.g. I find it essential to be able to mark messages as "Seen" as I file them. But roundcube is a good product under steady development, and I won't be at all surprised if they catch up or surpass ingo.
I've been using ingo and am happy with it, but to use it you have to install and configure the whole horde framework-- a good amount of work, and the only part of it I want is ingo.