[Zope] What groupware (not CMS) on top of Zope?

Hi, I juste asked on the Plone ML if it could be used as a groupware while CMS is its first feature. Andreas (thanks Andreas) aswered me it would be a good idea to look for a dedicated solution. I would like to stick on Zope and I am looking for a solution laying on it. My feature requests are: - A webmail - A shared and individual calendar - Some file management (~5MB/File, binary or not) that would allow me to make some files public or private. - A discussion tool Indexation (for Mail, discussion, calendar and files) is not a must, but would be appreciated. Is there any packaged (or easily packageable) solution you would know on top of Zope? Thank you.