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+==============
+Server support
+==============
+
+vdirsyncer is currently tested against the latest versions of Radicale and
+ownCloud.
+
+Radicale
+========
+
+Radicale doesn't `support time ranges in the calendar-query of CalDAV/CardDAV
+<https://github.com/Kozea/Radicale/issues/146>`_, so setting ``start_date`` and
+``end_date`` in vdirsyncer's configuration will have no or unpredicted
+consequences.
+
+ownCloud
+========
+
+ownCloud uses SabreDAV, which had problems detecting collisions and
+race-conditions. The problems were reported and are fixed in SabreDAV's repo.
+See `Bug #16 <https://github.com/untitaker/vdirsyncer/issues/16>`_ for more
+information.
+
+However, given that this is a problem with every setup involving ownCloud, and
+that ownCloud is widely used, it apparently isn't big enough of a problem yet.