For those who worried that the project was given up: relax! I was travelling for one month and that's why there were no releases and no answers. But now the development team is growing and we set up two mailing lists. Get more details at http://roundcube.net/?p=mailinglists
The latest nightly build with minor bugfixes and improvements of configuration and performance.
This nightly build comes up with a few new features such as folder management and selection/navigation functions.
The initial release is out now. It's just a development version and probably pretty buggy. Please report bugs to the bugtracking system at sourceforge.net.
Just added some screenshots showing the first alpha version in action. The webmail comes up with full featured multipart-message support as well as image blocking and an integrated address book.
Finally the project is opened at sourceforge.net. I'm still working on the project's website in order to provide more detailed informations about RoundCube Webmail. Anyhow, any help is appreciated because there's still a lot of work to be done! Thanks for your interest and come back soon...