I've been using 0.4 beta, because attaching a file is buggy in 0.3.1 (large files silently fail to attach). But there are still a few issues in 0.4-beta as well. My main question is why does roundcube not release more beta's as more issues are fixed. 0.4-beta was released in April, so it has almost been 4 months. And the fact that it's not called "beta1" suggests that there will be only one beta release, correct?
One thing that I see is that the virtuser_file plugin is either not well enough documented, or it's not working correctly. I have hardcoded the virtuser_file variable because when I added the config option to the global config option, it did not get it correctly. I really don't think that plugin variables should be stored in the main config anyways.
I love roundcube, and I understand that beta software really isn't for live environments, but I would think that there would be at least 2 or 3 beta's for something as important as mail software. That is just my suggestion though.
I'd be even happier to see a stable 0.4 released. Thanks for all of your work.