@bambam
I release the server is running. The settings I'm talking about are for the managesieve plugin for roundcube. while I don't think that is the issue, im wondering if the plugin is reading the correct set of parameters. If the trunk version checks for $rcmail_config['managesieve_port'] which in your case does not exist, it might try to connect on the default port and fail
just a thought. Also, johndoh's comments make sense. Something else to look into