Redmine

As there wqas a discussion on gantt chart across more projects (http://www.redmine.org/issues/1484) I wnat to stretch that topic for the calendar feature.
We are just starting redmine but we like it from the beginning since we made a lot of steps forward without need for technical assistance.
What I miss:
We do need a calendar for all projects. Is this a feature which already exists and I have not discovered yet or is it not there? It is important for planning and controlling the resources.
Thank you.