I have attempted several times to add a caldav source to Evolution, as described in http://www.google.com/support/calendar/bin/answer.py?answer=99358 for iCal on OSX, but the calendar is not accessible in Evolution. This is because the URI is severely munged, and invalid, due to the requirement of an @ in the user name, as well as one in the path element of the URI, in order to access the calendar. The username portion of the URI string appears to end up with several pieces of the username repeated over and over. Please fix this ASAP, so that people may manage their google calendars with caldav.