[SyncEvolution] sync failure

Hi, I've installed syncevolution on my N900, configuring it to sync to an egroupware server. I think I've correctly setup the config (I started from a Funambol config, changed the uris and types for the calendar/contacts/memo/todo and a few other tidbits). The starting state was: - a calendar on the server with just 1 test appointment. - the N900's addressbook rather full of contacts Now the addressbook contacts have correctly been copied from the N900 to the server, but the server's calendar didn't sync with the N900. Syncevolution reports failure for the sync, but I don't know why. Is that a known problem ? Is there some special config for that setup ? I saw that there are a bunch of files generated under /home/user/.cache, I may send them to you if it can help (and if they don't contain sensitive information). Thanks, Xav